diff --git a/dictation_server/db/migrations/053-add_accounts_users_templates_index.sql b/dictation_server/db/migrations/053-add_accounts_users_templates_index.sql
new file mode 100644
index 0000000..5b4a4a6
--- /dev/null
+++ b/dictation_server/db/migrations/053-add_accounts_users_templates_index.sql
@@ -0,0 +1,19 @@
+-- +migrate Up
+ALTER TABLE `accounts` ADD INDEX `idx_accounts_tier` (tier);
+ALTER TABLE `accounts` ADD INDEX `idx_accounts_parent_account_id` (parent_account_id);
+ALTER TABLE `users` ADD INDEX `idx_users_external_id` (external_id);
+ALTER TABLE `users` ADD INDEX `idx_users_email_verified` (email_verified);
+ALTER TABLE `licenses` ADD INDEX `idx_licenses_order_id` (order_id);
+ALTER TABLE `licenses` ADD INDEX `idx_licenses_status` (status);
+ALTER TABLE `template_files` ADD INDEX `idx_template_files_account_id` (account_id);
+ALTER TABLE `template_files` ADD INDEX `idx_template_files_file_name` (file_name(500));
+
+-- +migrate Down
+ALTER TABLE `accounts` DROP INDEX `idx_accounts_tier`;
+ALTER TABLE `accounts` DROP INDEX `idx_accounts_parent_account_id`;
+ALTER TABLE `users` DROP INDEX `idx_users_external_id`;
+ALTER TABLE `users` DROP INDEX `idx_users_email_verified`;
+ALTER TABLE `licenses` DROP INDEX `idx_licenses_order_id`;
+ALTER TABLE `licenses` DROP INDEX `idx_licenses_status`;
+ALTER TABLE `template_files` DROP INDEX `idx_template_files_account_id`;
+ALTER TABLE `template_files` DROP INDEX `idx_template_files_file_name`;
\ No newline at end of file
diff --git a/dictation_server/src/repositories/accounts/accounts.repository.service.ts b/dictation_server/src/repositories/accounts/accounts.repository.service.ts
index 6d7c758..2832672 100644
--- a/dictation_server/src/repositories/accounts/accounts.repository.service.ts
+++ b/dictation_server/src/repositories/accounts/accounts.repository.service.ts
@@ -821,6 +821,7 @@ export class AccountsRepositoryService {
           status: Not(LICENSE_ALLOCATED_STATUS.UNALLOCATED),
         },
         comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
+        lock: { mode: 'pessimistic_write' },
       });
 
       // 存在した場合エラー
@@ -1023,6 +1024,7 @@ export class AccountsRepositoryService {
             email_verified: true,
           },
           comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
+          lock: { mode: 'pessimistic_write' },
         });
         if (!primaryAdminUser) {
           throw new AdminUserNotFoundError(
@@ -1040,6 +1042,7 @@ export class AccountsRepositoryService {
             email_verified: true,
           },
           comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
+          lock: { mode: 'pessimistic_write' },
         });
         if (!secondryAdminUser) {
           throw new AdminUserNotFoundError(
diff --git a/dictation_server/src/repositories/licenses/licenses.repository.service.ts b/dictation_server/src/repositories/licenses/licenses.repository.service.ts
index 5aeb576..a5e03a3 100644
--- a/dictation_server/src/repositories/licenses/licenses.repository.service.ts
+++ b/dictation_server/src/repositories/licenses/licenses.repository.service.ts
@@ -12,7 +12,6 @@ import {
   LICENSE_ALLOCATED_STATUS,
   LICENSE_ISSUE_STATUS,
   LICENSE_TYPE,
-  NODE_ENV_TEST,
   SWITCH_FROM_TYPE,
   TIERS,
   USER_LICENSE_STATUS,
@@ -423,10 +422,7 @@ export class LicensesRepositoryService {
           po_number: poNumber,
         },
         comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
-        // テスト環境の場合はロックを行わない(sqliteがlockに対応していないため)
-        ...(process.env.NODE_ENV !== NODE_ENV_TEST
-          ? { lock: { mode: 'pessimistic_write' } }
-          : {}),
+        lock: { mode: 'pessimistic_write' },
       });
       if (!issuingOrder) {
         // 注文が存在しない場合、エラー
@@ -570,6 +566,7 @@ export class LicensesRepositoryService {
           id: newLicenseId,
         },
         comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
+        lock: { mode: 'pessimistic_write' },
       });
 
       // ライセンスが存在しない場合はエラー
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 e3d3319..5fc805b 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
@@ -52,6 +52,7 @@ export class TemplateFilesRepositoryService {
       const template = await templateFilesRepo.findOne({
         where: { account_id: accountId, file_name: fileName },
         comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
+        lock: { mode: 'pessimistic_write' },
       });
 
       // 同名ファイルは同じものとして扱うため、すでにファイルがあれば更新（更新日時の履歴を残しておきたい）
diff --git a/dictation_server/src/repositories/users/users.repository.service.ts b/dictation_server/src/repositories/users/users.repository.service.ts
index ae3fccc..8c39441 100644
--- a/dictation_server/src/repositories/users/users.repository.service.ts
+++ b/dictation_server/src/repositories/users/users.repository.service.ts
@@ -289,6 +289,7 @@ export class UsersRepositoryService {
       const targetUser = await repo.findOne({
         where: { id: id, account_id: accountId },
         comment: `${context.getTrackingId()}_${new Date().toUTCString()}`,
+        lock: { mode: 'pessimistic_write' },
       });
 
       // 運用上ユーザがいないことはあり得ないが、プログラム上発生しうるのでエラーとして処理