diff --git a/dictation_client/src/common/convertUtcToLocal.ts b/dictation_client/src/common/convertUtcToLocal.ts
new file mode 100644
index 0000000..bbb4c0b
--- /dev/null
+++ b/dictation_client/src/common/convertUtcToLocal.ts
@@ -0,0 +1,15 @@
+// UTCの日付に対してローカルのロケール＋タイムゾーンを考慮して表示形式と時刻補正を行った文字列を返却する
+export const convertUtcToLocal = (
+  utcDateString: string,
+  formatOptions?: Intl.DateTimeFormatOptions
+): string => {
+  if (Number.isNaN(Date.parse(utcDateString))) {
+    // 日付文字列が未定義または無効な場合は 変換を行わない
+    return utcDateString;
+  }
+
+  const utcDate = new Date(utcDateString);
+  return formatOptions
+    ? utcDate.toLocaleString(undefined, formatOptions)
+    : utcDate.toLocaleString();
+};
diff --git a/dictation_client/src/features/dictation/selectors.ts b/dictation_client/src/features/dictation/selectors.ts
index 3b6f494..41af21b 100644
--- a/dictation_client/src/features/dictation/selectors.ts
+++ b/dictation_client/src/features/dictation/selectors.ts
@@ -1,9 +1,50 @@
 import { RootState } from "app/store";
+import { convertUtcToLocal } from "common/convertUtcToLocal";
 import { ceil, floor } from "lodash";
 import { BACKUP_POPUP_LIST_SIZE } from "./constants";
 
-export const selectTasks = (state: RootState) => state.dictation.domain.tasks;
+// ミリ秒の数値をhh:mm:ss形式に変換する
+const formatMillisecondsToHHMMSS = (milliseconds: number): string => {
+  const seconds = Math.floor(milliseconds / 1000);
+  if (seconds < 0) {
+    return "00:00:00";
+  }
 
+  const hours = Math.floor(seconds / 3600);
+  const minutes = Math.floor((seconds % 3600) / 60);
+  const remainingSeconds = Math.floor(seconds % 60);
+
+  // "0x"となるように0埋めする
+  const formattedHours = String(hours).padStart(2, "0");
+  const formattedMinutes = String(minutes).padStart(2, "0");
+  const formattedSeconds = String(remainingSeconds).padStart(2, "0");
+
+  return `${formattedHours}:${formattedMinutes}:${formattedSeconds}`;
+};
+
+export const selectTasks = (state: RootState) => {
+  const { tasks } = state.dictation.domain;
+
+  const tasksWithLocalDate = tasks.map((task) => ({
+    ...task,
+
+    // UTCからローカルタイムゾーンに変換して詰めなおす
+    audioCreatedDate: convertUtcToLocal(task.audioCreatedDate),
+    audioFinishedDate: convertUtcToLocal(task.audioFinishedDate),
+    audioUploadedDate: convertUtcToLocal(task.audioUploadedDate),
+    transcriptionStartedDate:
+      task.transcriptionStartedDate &&
+      convertUtcToLocal(task.transcriptionStartedDate),
+    transcriptionFinishedDate:
+      task.transcriptionFinishedDate &&
+      convertUtcToLocal(task.transcriptionFinishedDate),
+
+    // ミリ秒からhh:mm:ss形式に変換して詰めなおす
+    audioDuration: formatMillisecondsToHHMMSS(parseInt(task.audioDuration, 10)),
+  }));
+
+  return tasksWithLocalDate;
+};
 export const selectTotal = (state: RootState) => state.dictation.domain.total;
 
 export const seletctLimit = (state: RootState) => state.dictation.domain.limit;
diff --git a/dictation_client/src/features/license/licenseOrderHistory/selectors.ts b/dictation_client/src/features/license/licenseOrderHistory/selectors.ts
index e3e4ceb..7903a5a 100644
--- a/dictation_client/src/features/license/licenseOrderHistory/selectors.ts
+++ b/dictation_client/src/features/license/licenseOrderHistory/selectors.ts
@@ -1,8 +1,27 @@
 import { RootState } from "app/store";
 import { ceil, floor } from "lodash";
+import { convertUtcToLocal } from "common/convertUtcToLocal";
 
-export const selectOrderHisory = (state: RootState) =>
-  state.licenseOrderHistory.domain.orderHistories;
+export const selectOrderHisory = (state: RootState) => {
+  const { orderHistories } = state.licenseOrderHistory.domain;
+
+  const dateOptions: Intl.DateTimeFormatOptions = {
+    year: "numeric",
+    month: "numeric",
+    day: "numeric",
+  };
+
+  const orderHistoriesWithLocalDate = orderHistories.map((orderHistory) => ({
+    ...orderHistory,
+    // UTCからローカルタイムゾーンに変換して詰めなおす
+    orderDate: convertUtcToLocal(orderHistory.orderDate, dateOptions),
+    issueDate:
+      orderHistory.issueDate &&
+      convertUtcToLocal(orderHistory.issueDate, dateOptions),
+  }));
+
+  return orderHistoriesWithLocalDate;
+};
 
 export const selectCompanyName = (state: RootState) =>
   state.licenseOrderHistory.domain.companyName;
diff --git a/dictation_server/src/features/accounts/accounts.service.ts b/dictation_server/src/features/accounts/accounts.service.ts
index 4e4b474..0a19cb9 100644
--- a/dictation_server/src/features/accounts/accounts.service.ts
+++ b/dictation_server/src/features/accounts/accounts.service.ts
@@ -430,14 +430,12 @@ export class AccountsService {
       } | params: { ` + `externalId: ${externalId}, };`,
     );
     try {
-      let userInfo: User;
-      userInfo = await this.usersRepository.findUserByExternalId(
+      const userInfo = await this.usersRepository.findUserByExternalId(
         context,
         externalId,
       );
 
-      let accountInfo: Account;
-      accountInfo = await this.accountRepository.findAccountById(
+      const accountInfo = await this.accountRepository.findAccountById(
         context,
         userInfo.account_id,
       );
@@ -948,7 +946,7 @@ export class AccountsService {
       for (const childPartnerLicenseFromRepository of getPartnerLicenseResult.childPartnerLicensesFromRepository) {
         const { allocatableLicenseWithMargin, expiringSoonLicense } =
           childPartnerLicenseFromRepository;
-        let childShortage: number = 0;
+        let childShortage = 0;
         if (childPartnerLicenseFromRepository.tier === TIERS.TIER5) {
           if (
             allocatableLicenseWithMargin === undefined ||
@@ -1031,16 +1029,10 @@ export class AccountsService {
         const returnLicenseOrder: LicenseOrder = {
           issueDate:
             licenseOrder.issued_at !== null
-              ? new Date(licenseOrder.issued_at)
-                  .toISOString()
-                  .substring(0, 10)
-                  .replace(/-/g, '/')
+              ? new Date(licenseOrder.issued_at).toISOString()
               : undefined,
           numberOfOrder: licenseOrder.quantity,
-          orderDate: new Date(licenseOrder.ordered_at)
-            .toISOString()
-            .substring(0, 10)
-            .replace(/-/g, '/'),
+          orderDate: new Date(licenseOrder.ordered_at).toISOString(),
           poNumber: licenseOrder.po_number,
           status: licenseOrder.status,
         };