diff --git a/dictation_server/db/migrations/059-add_tasks_template_index.sql b/dictation_server/db/migrations/059-add_tasks_template_index.sql
new file mode 100644
index 0000000..17a871c
--- /dev/null
+++ b/dictation_server/db/migrations/059-add_tasks_template_index.sql
@@ -0,0 +1,5 @@
+-- +migrate Up
+ALTER TABLE `tasks` ADD INDEX `idx_tasks_template_file_id` (template_file_id);
+
+-- +migrate Down
+ALTER TABLE `tasks` DROP INDEX `idx_tasks_template_file_id`;
\ No newline at end of file
diff --git a/dictation_server/src/common/error/code.ts b/dictation_server/src/common/error/code.ts
index b6ad2af..a789ab7 100644
--- a/dictation_server/src/common/error/code.ts
+++ b/dictation_server/src/common/error/code.ts
@@ -79,4 +79,7 @@ export const ErrorCodes = [
   'E015001', // タイピストグループ削除エラー（削除しようとしたタイピストグループがすでに削除済みだった）
   'E015002', // タイピストグループ削除エラー（削除しようとしたタイピストグループがWorkflowのTypist候補として指定されていた）
   'E015003', // タイピストグループ削除エラー（削除しようとしたタイピストグループがチェックアウト可能なタスクが存在した）
+  'E016001', // テンプレートファイル削除エラー（削除しようとしたテンプレートファイルがすでに削除済みだった）
+  'E016002', // テンプレートファイル削除エラー（削除しようとしたテンプレートファイルがWorkflowに指定されていた）
+  'E016003', // テンプレートファイル削除エラー（削除しようとしたテンプレートファイルが未完了のタスクに紐づいていた）
 ] as const;
diff --git a/dictation_server/src/common/error/message.ts b/dictation_server/src/common/error/message.ts
index 20a176f..793cdf5 100644
--- a/dictation_server/src/common/error/message.ts
+++ b/dictation_server/src/common/error/message.ts
@@ -68,4 +68,8 @@ export const errors: Errors = {
   E015001: 'Typist Group delete failed Error: already deleted',
   E015002: 'Typist Group delete failed Error: workflow assigned',
   E015003: 'Typist Group delete failed Error: checkout permission existed',
+  E016001: 'Template file delete failed Error: already deleted',
+  E016002: 'Template file delete failed Error: workflow assigned',
+  E016003:
+    'Template file delete failed Error: not finished task has template file',
 };
diff --git a/dictation_server/src/features/tasks/test/utility.ts b/dictation_server/src/features/tasks/test/utility.ts
index 1d8efc9..d9e6d8f 100644
--- a/dictation_server/src/features/tasks/test/utility.ts
+++ b/dictation_server/src/features/tasks/test/utility.ts
@@ -273,6 +273,16 @@ export const getTask = async (
   return task;
 };
 
+export const getTasks = async (
+  datasource: DataSource,
+  account_id: number,
+): Promise<Task[]> => {
+  const tasks = await datasource.getRepository(Task).find({
+    where: { account_id: account_id },
+  });
+  return tasks;
+};
+
 export const getCheckoutPermissions = async (
   datasource: DataSource,
   task_id: number,
diff --git a/dictation_server/src/features/templates/templates.controller.ts b/dictation_server/src/features/templates/templates.controller.ts
index f4dce06..e98bcdf 100644
--- a/dictation_server/src/features/templates/templates.controller.ts
+++ b/dictation_server/src/features/templates/templates.controller.ts
@@ -18,7 +18,11 @@ import {
 import jwt from 'jsonwebtoken';
 import { AccessToken } from '../../common/token';
 import { ErrorResponse } from '../../common/error/types/types';
-import { DeleteTemplateRequestParam, DeleteTemplateResponse, GetTemplatesResponse } from './types/types';
+import {
+  DeleteTemplateRequestParam,
+  DeleteTemplateResponse,
+  GetTemplatesResponse,
+} from './types/types';
 import { AuthGuard } from '../../common/guards/auth/authguards';
 import { RoleGuard } from '../../common/guards/role/roleguards';
 import { ADMIN_ROLES } from '../../constants';
@@ -132,7 +136,7 @@ export class TemplatesController {
     RoleGuard.requireds({ roles: [ADMIN_ROLES.ADMIN], delegation: true }),
   )
   @Post(':templateFileId/delete')
-  async deleteTypistGroup(
+  async deleteTemplateFile(
     @Req() req: Request,
     @Param() param: DeleteTemplateRequestParam,
   ): Promise<DeleteTemplateResponse> {
@@ -174,7 +178,7 @@ export class TemplatesController {
     const context = makeContext(userId, requestId);
     this.logger.log(`[${context.getTrackingId()}] ip : ${ip}`);
 
-    // TODO: service層呼び出し
+    await this.templatesService.deleteTemplate(context, userId, templateFileId);
 
     return {};
   }
diff --git a/dictation_server/src/features/templates/templates.module.ts b/dictation_server/src/features/templates/templates.module.ts
index ac14580..fb93de7 100644
--- a/dictation_server/src/features/templates/templates.module.ts
+++ b/dictation_server/src/features/templates/templates.module.ts
@@ -3,9 +3,14 @@ import { TemplatesController } from './templates.controller';
 import { TemplatesService } from './templates.service';
 import { UsersRepositoryModule } from '../../repositories/users/users.repository.module';
 import { TemplateFilesRepositoryModule } from '../../repositories/template_files/template_files.repository.module';
+import { BlobstorageModule } from '../../gateways/blobstorage/blobstorage.module';
 
 @Module({
-  imports: [UsersRepositoryModule, TemplateFilesRepositoryModule],
+  imports: [
+    UsersRepositoryModule,
+    TemplateFilesRepositoryModule,
+    BlobstorageModule,
+  ],
   providers: [TemplatesService],
   controllers: [TemplatesController],
 })
diff --git a/dictation_server/src/features/templates/templates.service.spec.ts b/dictation_server/src/features/templates/templates.service.spec.ts
index 8ef101f..46dadf7 100644
--- a/dictation_server/src/features/templates/templates.service.spec.ts
+++ b/dictation_server/src/features/templates/templates.service.spec.ts
@@ -1,13 +1,26 @@
 import { DataSource } from 'typeorm';
 import { makeTestingModule } from '../../common/test/modules';
 import { TemplatesService } from './templates.service';
-import { createTemplateFile } from './test/utility';
-import { makeTestAccount } from '../../common/test/utility';
+import {
+  createTemplateFile,
+  getTemplateFiles,
+  updateTaskTemplateFile,
+} from './test/utility';
+import { makeTestAccount, makeTestUser } from '../../common/test/utility';
 import { makeContext } from '../../common/log';
 import { TemplateFilesRepositoryService } from '../../repositories/template_files/template_files.repository.service';
 import { HttpException, HttpStatus } from '@nestjs/common';
 import { makeErrorResponse } from '../../common/error/makeErrorResponse';
 import { truncateAllTable } from '../../common/test/init';
+import { overrideBlobstorageService } from '../../common/test/overrides';
+import { TASK_STATUS, USER_ROLES } from '../../constants';
+import { createTask, getTasks } from '../tasks/test/utility';
+import {
+  createWorkflow,
+  createWorkflowTypist,
+  getWorkflow,
+} from '../workflows/test/utility';
+import { BlobstorageService } from '../../gateways/blobstorage/blobstorage.service';
 
 describe('getTemplates', () => {
   let source: DataSource | null = null;
@@ -129,3 +142,355 @@ describe('getTemplates', () => {
     }
   });
 });
+
+describe('deleteTemplate', () => {
+  let source: DataSource | null = null;
+  beforeAll(async () => {
+    if (source == null) {
+      source = await (async () => {
+        const s = new DataSource({
+          type: 'mysql',
+          host: 'test_mysql_db',
+          port: 3306,
+          username: 'user',
+          password: 'password',
+          database: 'odms',
+          entities: [__dirname + '/../../**/*.entity{.ts,.js}'],
+          synchronize: false, // trueにすると自動的にmigrationが行われるため注意
+        });
+        return await s.initialize();
+      })();
+    }
+  });
+
+  beforeEach(async () => {
+    if (source) {
+      await truncateAllTable(source);
+    }
+  });
+
+  afterAll(async () => {
+    await source?.destroy();
+    source = null;
+  });
+
+  it('指定したテンプレートファイルを削除できる', async () => {
+    if (!source) fail();
+    const module = await makeTestingModule(source);
+    if (!module) fail();
+
+    const service = module.get<TemplatesService>(TemplatesService);
+    const blobStorageService =
+      module.get<BlobstorageService>(BlobstorageService);
+    overrideBlobstorageService(service, {
+      deleteFile: jest.fn(),
+    });
+
+    // 第五階層のアカウント作成
+    const { account, admin } = await makeTestAccount(source, { tier: 5 });
+    const { id: authorId } = await makeTestUser(source, {
+      account_id: account.id,
+      role: USER_ROLES.AUTHOR,
+      author_id: 'authorId',
+    });
+    const context = makeContext(admin.external_id, 'requestId');
+
+    const template1 = await createTemplateFile(
+      source,
+      account.id,
+      'test1',
+      'https://url1/test1',
+    );
+    const template2 = await createTemplateFile(
+      source,
+      account.id,
+      'test2',
+      'https://url2/test2',
+    );
+
+    const { taskId: taskId1 } = await createTask(
+      source,
+      account.id,
+      authorId,
+      'authorId',
+      '',
+      '01',
+      '00000001',
+      TASK_STATUS.FINISHED,
+    );
+    await updateTaskTemplateFile(source, taskId1, template1.id);
+
+    const { taskId: taskId2 } = await createTask(
+      source,
+      account.id,
+      authorId,
+      'authorId',
+      '',
+      '01',
+      '00000002',
+      TASK_STATUS.BACKUP,
+    );
+    await updateTaskTemplateFile(source, taskId2, template1.id);
+
+    // 作成したデータを確認
+    {
+      const templates = await getTemplateFiles(source, account.id);
+      expect(templates.length).toBe(2);
+      expect(templates[0].id).toBe(template1.id);
+      expect(templates[0].file_name).toBe(template1.file_name);
+      expect(templates[1].id).toBe(template2.id);
+      expect(templates[1].file_name).toBe(template2.file_name);
+
+      const tasks = await getTasks(source, account.id);
+      expect(tasks.length).toBe(2);
+      expect(tasks[0].template_file_id).toBe(template1.id);
+      expect(tasks[1].template_file_id).toBe(template1.id);
+    }
+
+    await service.deleteTemplate(context, admin.external_id, template1.id);
+
+    //実行結果を確認
+    {
+      const templates = await getTemplateFiles(source, account.id);
+      expect(templates.length).toBe(1);
+      expect(templates[0].id).toBe(template2.id);
+      expect(templates[0].file_name).toBe(template2.file_name);
+
+      const tasks = await getTasks(source, account.id);
+      expect(tasks.length).toBe(2);
+      expect(tasks[0].template_file_id).toBe(null);
+      expect(tasks[1].template_file_id).toBe(null);
+
+      // Blob削除メソッドが呼ばれているか確認
+      expect(blobStorageService.deleteFile).toBeCalledWith(
+        context,
+        account.id,
+        account.country,
+        'Templates/test1',
+      );
+    }
+  });
+
+  it('指定したテンプレートファイルが存在しない場合、400エラーとなる', async () => {
+    if (!source) fail();
+    const module = await makeTestingModule(source);
+    if (!module) fail();
+
+    const service = module.get<TemplatesService>(TemplatesService);
+    overrideBlobstorageService(service, {
+      deleteFile: jest.fn(),
+    });
+
+    // 第五階層のアカウント作成
+    const { account, admin } = await makeTestAccount(source, { tier: 5 });
+
+    const context = makeContext(admin.external_id, 'requestId');
+
+    const template1 = await createTemplateFile(
+      source,
+      account.id,
+      'test1',
+      'https://url1/test1',
+    );
+
+    // 作成したデータを確認
+    {
+      const templates = await getTemplateFiles(source, account.id);
+      expect(templates.length).toBe(1);
+      expect(templates[0].id).toBe(template1.id);
+      expect(templates[0].file_name).toBe(template1.file_name);
+    }
+
+    //実行結果を確認
+    try {
+      await service.deleteTemplate(context, admin.external_id, 9999);
+      fail();
+    } catch (e) {
+      if (e instanceof HttpException) {
+        expect(e.getStatus()).toEqual(HttpStatus.BAD_REQUEST);
+        expect(e.getResponse()).toEqual(makeErrorResponse('E016001'));
+      } else {
+        fail();
+      }
+    }
+  });
+
+  it('指定したテンプレートファイルがルーティングルールに紐づく場合、400エラーとなる', async () => {
+    if (!source) fail();
+    const module = await makeTestingModule(source);
+    if (!module) fail();
+
+    const service = module.get<TemplatesService>(TemplatesService);
+    overrideBlobstorageService(service, {
+      deleteFile: jest.fn(),
+    });
+
+    // 第五階層のアカウント作成
+    const { account, admin } = await makeTestAccount(source, { tier: 5 });
+    const { id: authorId } = await makeTestUser(source, {
+      account_id: account.id,
+      role: USER_ROLES.AUTHOR,
+      author_id: 'authorId',
+    });
+    const { id: typistId } = await makeTestUser(source, {
+      account_id: account.id,
+      role: USER_ROLES.TYPIST,
+    });
+    const context = makeContext(admin.external_id, 'requestId');
+
+    const template1 = await createTemplateFile(
+      source,
+      account.id,
+      'test1',
+      'https://url1/test1',
+    );
+
+    const { id: workflowId } = await createWorkflow(
+      source,
+      account.id,
+      authorId,
+      undefined,
+      template1.id,
+    );
+    await createWorkflowTypist(source, workflowId, typistId);
+
+    // 作成したデータを確認
+    {
+      const templates = await getTemplateFiles(source, account.id);
+      expect(templates.length).toBe(1);
+      expect(templates[0].id).toBe(template1.id);
+      expect(templates[0].file_name).toBe(template1.file_name);
+
+      const workflow = await getWorkflow(source, account.id, workflowId);
+      expect(workflow?.template_id).toBe(template1.id);
+    }
+
+    //実行結果を確認
+    try {
+      await service.deleteTemplate(context, admin.external_id, template1.id);
+      fail();
+    } catch (e) {
+      if (e instanceof HttpException) {
+        expect(e.getStatus()).toEqual(HttpStatus.BAD_REQUEST);
+        expect(e.getResponse()).toEqual(makeErrorResponse('E016002'));
+      } else {
+        fail();
+      }
+    }
+  });
+
+  it('指定したテンプレートファイルが未完了のタスクに紐づく場合、400エラーとなる', async () => {
+    if (!source) fail();
+    const module = await makeTestingModule(source);
+    if (!module) fail();
+
+    const service = module.get<TemplatesService>(TemplatesService);
+    overrideBlobstorageService(service, {
+      deleteFile: jest.fn(),
+    });
+
+    // 第五階層のアカウント作成
+    const { account, admin } = await makeTestAccount(source, { tier: 5 });
+    const { id: authorId } = await makeTestUser(source, {
+      account_id: account.id,
+      role: USER_ROLES.AUTHOR,
+      author_id: 'authorId',
+    });
+    const context = makeContext(admin.external_id, 'requestId');
+
+    const template1 = await createTemplateFile(
+      source,
+      account.id,
+      'test1',
+      'https://url1/test1',
+    );
+
+    const { taskId: taskId1 } = await createTask(
+      source,
+      account.id,
+      authorId,
+      'authorId',
+      '',
+      '01',
+      '00000001',
+      TASK_STATUS.UPLOADED,
+    );
+    await updateTaskTemplateFile(source, taskId1, template1.id);
+
+    // 作成したデータを確認
+    {
+      const templates = await getTemplateFiles(source, account.id);
+      expect(templates.length).toBe(1);
+      expect(templates[0].id).toBe(template1.id);
+      expect(templates[0].file_name).toBe(template1.file_name);
+
+      const tasks = await getTasks(source, account.id);
+      expect(tasks.length).toBe(1);
+      expect(tasks[0].template_file_id).toBe(template1.id);
+      expect(tasks[0].status).toBe(TASK_STATUS.UPLOADED);
+    }
+
+    //実行結果を確認
+    try {
+      await service.deleteTemplate(context, admin.external_id, template1.id);
+      fail();
+    } catch (e) {
+      if (e instanceof HttpException) {
+        expect(e.getStatus()).toEqual(HttpStatus.BAD_REQUEST);
+        expect(e.getResponse()).toEqual(makeErrorResponse('E016003'));
+      } else {
+        fail();
+      }
+    }
+  });
+
+  it('DBアクセスに失敗した場合、500エラーとなる', async () => {
+    if (!source) fail();
+    const module = await makeTestingModule(source);
+    if (!module) fail();
+
+    const service = module.get<TemplatesService>(TemplatesService);
+    overrideBlobstorageService(service, {
+      deleteFile: jest.fn(),
+    });
+
+    // 第五階層のアカウント作成
+    const { account, admin } = await makeTestAccount(source, { tier: 5 });
+    const context = makeContext(admin.external_id, 'requestId');
+
+    const template1 = await createTemplateFile(
+      source,
+      account.id,
+      'test1',
+      'https://url1/test1',
+    );
+
+    // 作成したデータを確認
+    {
+      const templates = await getTemplateFiles(source, account.id);
+      expect(templates.length).toBe(1);
+      expect(templates[0].id).toBe(template1.id);
+      expect(templates[0].file_name).toBe(template1.file_name);
+    }
+
+    //DBアクセスに失敗するようにする
+    const templateFilesRepositoryService =
+      module.get<TemplateFilesRepositoryService>(
+        TemplateFilesRepositoryService,
+      );
+    templateFilesRepositoryService.getTemplateFiles = jest
+      .fn()
+      .mockRejectedValue('DB failed');
+
+    try {
+      await service.deleteTemplate(context, admin.external_id, template1.id);
+    } catch (e) {
+      if (e instanceof HttpException) {
+        expect(e.getStatus()).toEqual(HttpStatus.INTERNAL_SERVER_ERROR);
+        expect(e.getResponse()).toEqual(makeErrorResponse('E009999'));
+      } else {
+        fail();
+      }
+    }
+  });
+});
diff --git a/dictation_server/src/features/templates/templates.service.ts b/dictation_server/src/features/templates/templates.service.ts
index ae36afe..36b2549 100644
--- a/dictation_server/src/features/templates/templates.service.ts
+++ b/dictation_server/src/features/templates/templates.service.ts
@@ -4,6 +4,13 @@ import { TemplateFile } from './types/types';
 import { Context } from '../../common/log';
 import { makeErrorResponse } from '../../common/error/makeErrorResponse';
 import { TemplateFilesRepositoryService } from '../../repositories/template_files/template_files.repository.service';
+import {
+  NotFinishedTaskHasTemplateDeleteFailedError,
+  TemplateFileNotExistError,
+  WorkflowHasTemplateDeleteFailedError,
+} from '../../repositories/template_files/errors/types';
+import { BlobstorageService } from '../../gateways/blobstorage/blobstorage.service';
+import { MANUAL_RECOVERY_REQUIRED } from '../../constants';
 
 @Injectable()
 export class TemplatesService {
@@ -11,6 +18,7 @@ export class TemplatesService {
   constructor(
     private readonly usersRepository: UsersRepositoryService,
     private readonly templateFilesRepository: TemplateFilesRepositoryService,
+    private readonly blobStorageService: BlobstorageService,
   ) {}
 
   /**
@@ -55,4 +63,103 @@ export class TemplatesService {
       );
     }
   }
+
+  /**
+   * アカウント内の指定されたテンプレートファイルを削除する
+   * @param context
+   * @param externalId
+   * @param templateFileId
+   * @returns template
+   */
+  async deleteTemplate(
+    context: Context,
+    externalId: string,
+    templateFileId: number,
+  ): Promise<void> {
+    this.logger.log(
+      `[IN] [${context.getTrackingId()}] ${
+        this.deleteTemplate.name
+      } | params: { externalId: ${externalId}, templateFileId: ${templateFileId} };`,
+    );
+
+    try {
+      const { account } = await this.usersRepository.findUserByExternalId(
+        context,
+        externalId,
+      );
+
+      if (!account) {
+        throw new Error(`account not found. externalId: ${externalId}`);
+      }
+
+      // テンプレートファイルの取得
+      const templateFile = await this.templateFilesRepository.getTemplateFile(
+        context,
+        account.id,
+        templateFileId,
+      );
+
+      // DBからのテンプレートファイルの削除
+      await this.templateFilesRepository.deleteTemplateFile(
+        context,
+        account.id,
+        templateFileId,
+      );
+
+      try {
+        // Blob Storageからのテンプレートファイルの削除
+        await this.blobStorageService.deleteFile(
+          context,
+          account.id,
+          account.country,
+          `Templates/${templateFile.file_name}`,
+        );
+      } catch (e) {
+        // Blob削除失敗時は、MANUAL_RECOVERY_REQUIREDを出して処理続行
+        this.logger.log(`[${context.getTrackingId()}] ${e}`);
+        this.logger.log(
+          `${MANUAL_RECOVERY_REQUIRED} [${context.getTrackingId()}] Failed to delete Blob: accountId: ${
+            account.id
+          }, fileName: ${templateFile.file_name}`,
+        );
+      }
+    } catch (e) {
+      this.logger.error(`[${context.getTrackingId()}] error=${e}`);
+      if (e instanceof Error) {
+        switch (e.constructor) {
+          // 指定されたIDのテンプレートファイルが存在しない
+          case TemplateFileNotExistError:
+            throw new HttpException(
+              makeErrorResponse('E016001'),
+              HttpStatus.BAD_REQUEST,
+            );
+          // 指定されたIDのテンプレートファイルがルーティングルールに設定されている
+          case WorkflowHasTemplateDeleteFailedError:
+            throw new HttpException(
+              makeErrorResponse('E016002'),
+              HttpStatus.BAD_REQUEST,
+            );
+          // 指定されたIDのテンプレートファイルが未完了タスクに紐づいている
+          case NotFinishedTaskHasTemplateDeleteFailedError:
+            throw new HttpException(
+              makeErrorResponse('E016003'),
+              HttpStatus.BAD_REQUEST,
+            );
+          default:
+            throw new HttpException(
+              makeErrorResponse('E009999'),
+              HttpStatus.INTERNAL_SERVER_ERROR,
+            );
+        }
+      }
+      throw new HttpException(
+        makeErrorResponse('E009999'),
+        HttpStatus.INTERNAL_SERVER_ERROR,
+      );
+    } finally {
+      this.logger.log(
+        `[OUT] [${context.getTrackingId()}] ${this.deleteTemplate.name}`,
+      );
+    }
+  }
 }
diff --git a/dictation_server/src/features/templates/test/utility.ts b/dictation_server/src/features/templates/test/utility.ts
index 224b536..1358df1 100644
--- a/dictation_server/src/features/templates/test/utility.ts
+++ b/dictation_server/src/features/templates/test/utility.ts
@@ -1,5 +1,6 @@
 import { DataSource } from 'typeorm';
 import { TemplateFile } from '../../../repositories/template_files/entity/template_file.entity';
+import { Task } from '../../../repositories/tasks/entity/task.entity';
 
 export const createTemplateFile = async (
   datasource: DataSource,
@@ -41,3 +42,18 @@ export const getTemplateFiles = async (
   });
   return templates;
 };
+
+export const updateTaskTemplateFile = async (
+  datasource: DataSource,
+  taskId: number,
+  templateFileId: number,
+): Promise<void> => {
+  await datasource.getRepository(Task).update(
+    { id: taskId },
+    {
+      template_file_id: templateFileId,
+      updated_by: 'updater',
+      updated_at: new Date(),
+    },
+  );
+};
diff --git a/dictation_server/src/repositories/template_files/errors/types.ts b/dictation_server/src/repositories/template_files/errors/types.ts
index d1db4d7..9cff27f 100644
--- a/dictation_server/src/repositories/template_files/errors/types.ts
+++ b/dictation_server/src/repositories/template_files/errors/types.ts
@@ -5,3 +5,17 @@ export class TemplateFileNotExistError extends Error {
     this.name = 'TemplateFileNotExistError';
   }
 }
+
+export class WorkflowHasTemplateDeleteFailedError extends Error {
+  constructor(message: string) {
+    super(message);
+    this.name = 'WorkflowHasTemplateDeleteFailedError';
+  }
+}
+
+export class NotFinishedTaskHasTemplateDeleteFailedError extends Error {
+  constructor(message: string) {
+    super(message);
+    this.name = 'NotFinishedTaskHasTemplateDeleteFailedError';
+  }
+}
diff --git a/dictation_server/src/repositories/template_files/template_files.repository.service.ts b/dictation_server/src/repositories/template_files/template_files.repository.service.ts
index 5fc805b..c1ec96c 100644
--- a/dictation_server/src/repositories/template_files/template_files.repository.service.ts
+++ b/dictation_server/src/repositories/template_files/template_files.repository.service.ts
@@ -1,8 +1,20 @@
 import { Injectable } from '@nestjs/common';
-import { DataSource } from 'typeorm';
+import { DataSource, In } from 'typeorm';
 import { TemplateFile } from './entity/template_file.entity';
-import { insertEntity, updateEntity } from '../../common/repository';
+import {
+  deleteEntity,
+  insertEntity,
+  updateEntity,
+} from '../../common/repository';
 import { Context } from '../../common/log';
+import {
+  NotFinishedTaskHasTemplateDeleteFailedError,
+  TemplateFileNotExistError,
+  WorkflowHasTemplateDeleteFailedError,
+} from './errors/types';
+import { Workflow } from '../workflows/entity/workflow.entity';
+import { Task } from '../tasks/entity/task.entity';
+import { TASK_STATUS } from '../../constants';
 
 @Injectable()
 export class TemplateFilesRepositoryService {
@@ -32,6 +44,36 @@ export class TemplateFilesRepositoryService {
     });
   }
 
+  /**
+   * アカウント内のIDで指定されたテンプレートファイルを取得する
+   * @param context
+   * @param accountId
+   * @param templateFileId
+   * @returns template file
+   */
+  async getTemplateFile(
+    context: Context,
+    accountId: number,
+    templateFileId: number,
+  ): Promise<TemplateFile> {
+    return await this.dataSource.transaction(async (entityManager) => {
+      const templateFilesRepo = entityManager.getRepository(TemplateFile);
+
+      const template = await templateFilesRepo.findOne({
+        where: { account_id: accountId, id: templateFileId },
+        comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
+      });
+
+      if (!template) {
+        throw new TemplateFileNotExistError(
+          `template file not found. accountId: ${accountId}, templateFileId: ${templateFileId}`,
+        );
+      }
+
+      return template;
+    });
+  }
+
   /**
    * アカウント内にテンプレートファイルを追加（すでに同名ファイルがあれば更新）する
    * @param accountId
@@ -79,4 +121,92 @@ export class TemplateFilesRepositoryService {
       }
     });
   }
+
+  /**
+   * アカウント内にある指定されたテンプレートファイルを削除する
+   * @param accountId
+   * @param fileName
+   * @param url
+   * @returns template file
+   */
+  async deleteTemplateFile(
+    context: Context,
+    accountId: number,
+    templateFileId: number,
+  ): Promise<void> {
+    await this.dataSource.transaction(async (entityManager) => {
+      const workflowRepo = entityManager.getRepository(Workflow);
+      // テンプレートファイルがワークフローで使用されているか確認
+      const workflow = await workflowRepo.findOne({
+        where: {
+          account_id: accountId,
+          template_id: templateFileId,
+        },
+        lock: { mode: 'pessimistic_write' },
+        comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
+      });
+
+      // ワークフローで使用されている場合はエラー
+      if (workflow) {
+        throw new WorkflowHasTemplateDeleteFailedError(
+          `workflow has template file. accountId: ${accountId}, templateFileId: ${templateFileId}`,
+        );
+      }
+
+      const templateFilesRepo = entityManager.getRepository(TemplateFile);
+      // アカウント内に指定IDファイルがあるか確認
+      const template = await templateFilesRepo.findOne({
+        where: { account_id: accountId, id: templateFileId },
+        lock: { mode: 'pessimistic_write' },
+        comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
+      });
+
+      // ファイルが存在しない場合はエラー
+      if (!template) {
+        throw new TemplateFileNotExistError(
+          `template file not found. accountId: ${accountId}, templateFileId: ${templateFileId}`,
+        );
+      }
+
+      const taskRepo = entityManager.getRepository(Task);
+      // テンプレートファイルが未完了タスクで使用されているか確認
+      const templateUsedTasks = await taskRepo.findOne({
+        where: {
+          account_id: accountId,
+          template_file_id: templateFileId,
+          status: In([
+            TASK_STATUS.UPLOADED,
+            TASK_STATUS.IN_PROGRESS,
+            TASK_STATUS.PENDING,
+          ]),
+        },
+        lock: { mode: 'pessimistic_write' },
+        comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
+      });
+
+      // 未完了のタスクでテンプレートファイルが使用されている場合はエラー
+      if (templateUsedTasks) {
+        throw new NotFinishedTaskHasTemplateDeleteFailedError(
+          `not finished task has template file. accountId: ${accountId}, templateFileId: ${templateFileId}`,
+        );
+      }
+
+      // テンプレートファイルの削除
+      await deleteEntity(
+        templateFilesRepo,
+        { id: templateFileId },
+        this.isCommentOut,
+        context,
+      );
+
+      // 完了済みのタスクからテンプレートファイルの紐づけを解除
+      await updateEntity(
+        taskRepo,
+        { template_file_id: templateFileId },
+        { template_file_id: null },
+        this.isCommentOut,
+        context,
+      );
+    });
+  }
 }