diff --git a/dictation_client/src/common/errors/code.ts b/dictation_client/src/common/errors/code.ts
index 41368a5..8c3236f 100644
--- a/dictation_client/src/common/errors/code.ts
+++ b/dictation_client/src/common/errors/code.ts
@@ -56,4 +56,5 @@ export const errorCodes = [
   "E011002", // ワークタイプ登録上限超過エラー
   "E011003", // ワークタイプ不在エラー
   "E013001", // ワークフローのAuthorIDとWorktypeIDのペア重複エラー
+  "E013002", // ワークフロー不在エラー
 ] as const;
diff --git a/dictation_client/src/features/workflow/operations.ts b/dictation_client/src/features/workflow/operations.ts
index 7b11e04..01a9815 100644
--- a/dictation_client/src/features/workflow/operations.ts
+++ b/dictation_client/src/features/workflow/operations.ts
@@ -346,6 +346,17 @@ export const deleteWorkflowAsync = createAsyncThunk<
     // e ⇒ errorObjectに変換"
     const error = createErrorObject(e);
 
+    // ワークフローが削除済みの場合は成功扱いとする
+    if (error.code === "E013002") {
+      thunkApi.dispatch(
+        openSnackbar({
+          level: "info",
+          message: getTranslationID("common.message.success"),
+        })
+      );
+      return {};
+    }
+
     thunkApi.dispatch(
       openSnackbar({
         level: "error",