diff --git a/src/background.ts b/src/background.ts
index 0b6b78a700..9cd5663c9b 100644
--- a/src/background.ts
+++ b/src/background.ts
@@ -324,12 +324,6 @@ async function uninstallVvppEngine(engineId: EngineId) {
   }
 }
 
-// temp dir
-const tempDir = path.join(app.getPath("temp"), "VOICEVOX");
-if (!fs.existsSync(tempDir)) {
-  fs.mkdirSync(tempDir);
-}
-
 // 使い方テキストの読み込み
 const howToUseText = fs.readFileSync(
   path.join(__static, "howtouse.md"),
@@ -563,10 +557,6 @@ ipcMainHandle("GET_APP_INFOS", () => {
   };
 });
 
-ipcMainHandle("GET_TEMP_DIR", () => {
-  return tempDir;
-});
-
 ipcMainHandle("GET_HOW_TO_USE_TEXT", () => {
   return howToUseText;
 });
@@ -875,10 +865,6 @@ ipcMainHandle("WRITE_FILE", (_, { filePath, buffer }) => {
   return undefined;
 });
 
-ipcMainHandle("JOIN_PATH", (_, { pathArray }) => {
-  return path.join(...pathArray);
-});
-
 ipcMainHandle("READ_FILE", (_, { filePath }) => {
   return fs.promises.readFile(filePath);
 });
diff --git a/src/electron/preload.ts b/src/electron/preload.ts
index bb083f5e74..38ed5a9e48 100644
--- a/src/electron/preload.ts
+++ b/src/electron/preload.ts
@@ -32,8 +32,6 @@ function ipcRendererOn(
   return ipcRenderer.on(channel, listener);
 }
 
-let tempDir: string;
-
 const api: Sandbox = {
   getAppInfos: async () => {
     return await ipcRendererInvoke("GET_APP_INFOS");
@@ -75,32 +73,6 @@ const api: Sandbox = {
     return await ipcRendererInvoke("GET_ALT_PORT_INFOS");
   },
 
-  saveTempAudioFile: async ({ relativePath, buffer }) => {
-    if (!tempDir) {
-      tempDir = await ipcRendererInvoke("GET_TEMP_DIR");
-    }
-    const tempFilePath = await ipcRendererInvoke("JOIN_PATH", {
-      pathArray: [tempDir, relativePath],
-    });
-    await ipcRendererInvoke("WRITE_FILE", {
-      filePath: tempFilePath,
-      buffer: buffer,
-    });
-  },
-
-  loadTempFile: async () => {
-    if (!tempDir) {
-      tempDir = await ipcRendererInvoke("GET_TEMP_DIR");
-    }
-    const tempFilePath = await ipcRendererInvoke("JOIN_PATH", {
-      pathArray: [tempDir, "hoge.txt"],
-    });
-    const buf = await ipcRendererInvoke("READ_FILE", {
-      filePath: tempFilePath,
-    });
-    return new TextDecoder().decode(buf);
-  },
-
   showAudioSaveDialog: ({ title, defaultPath }) => {
     return ipcRendererInvoke("SHOW_AUDIO_SAVE_DIALOG", { title, defaultPath });
   },
diff --git a/src/type/ipc.ts b/src/type/ipc.ts
index 6309a30a52..8e3454a5ad 100644
--- a/src/type/ipc.ts
+++ b/src/type/ipc.ts
@@ -24,11 +24,6 @@ export type IpcIHData = {
     return: AppInfos;
   };
 
-  GET_TEMP_DIR: {
-    args: [];
-    return: string;
-  };
-
   GET_HOW_TO_USE_TEXT: {
     args: [];
     return: string;
@@ -297,11 +292,6 @@ export type IpcIHData = {
     return: void;
   };
 
-  JOIN_PATH: {
-    args: [obj: { pathArray: string[] }];
-    return: string;
-  };
-
   WRITE_FILE: {
     args: [obj: { filePath: string; buffer: ArrayBuffer }];
     return: WriteFileErrorResult | undefined;
diff --git a/src/type/preload.ts b/src/type/preload.ts
index ccae077555..73ed65e1ca 100644
--- a/src/type/preload.ts
+++ b/src/type/preload.ts
@@ -144,8 +144,6 @@ export interface Sandbox {
   getContactText(): Promise<string>;
   getPrivacyPolicyText(): Promise<string>;
   getAltPortInfos(): Promise<AltPortInfos>;
-  saveTempAudioFile(obj: { relativePath: string; buffer: ArrayBuffer }): void;
-  loadTempFile(): Promise<string>;
   showAudioSaveDialog(obj: {
     title: string;
     defaultPath?: string;