diff --git a/lib/plugin/utils/plugin-utils.ts b/lib/plugin/utils/plugin-utils.ts
index 33bfe414a..7d1bd208b 100644
--- a/lib/plugin/utils/plugin-utils.ts
+++ b/lib/plugin/utils/plugin-utils.ts
@@ -125,7 +125,7 @@ export function getTypeReferenceAsString(
 }
 
 export function isPromiseOrObservable(type: string) {
-  return type.includes('Promise') || type.includes('Observable');
+  return type.includes('Promise<') || type.includes('Observable<');
 }
 
 export function hasPropertyKey(
diff --git a/test/plugin/fixtures/app.controller.ts b/test/plugin/fixtures/app.controller.ts
index e407a9db7..a73ae0731 100644
--- a/test/plugin/fixtures/app.controller.ts
+++ b/test/plugin/fixtures/app.controller.ts
@@ -3,6 +3,10 @@ import { ApiOperation } from '@nestjs/swagger';
 
 class Cat {}
 
+class PromiseCat {}
+
+class ObservableCat {}
+
 @Controller('cats')
 export class AppController {
   onApplicationBootstrap() {}
@@ -39,6 +43,24 @@ export class AppController {
   @Post()
   async testCreate2(): Promise<Cat> {}
 
+  /**
+   * create a test PromiseCat
+   *
+   * @returns {Promise<PromiseCat>>}
+   * @memberof AppController
+   */
+  @Post()
+  async testCreate3(): Promise<PromiseCat> {}
+
+  /**
+   * create a test ObservableCat
+   *
+   * @returns {Promise<ObservableCat>}
+   * @memberof AppController
+   */
+  @Post()
+  async testCreate4(): Promise<ObservableCat> {}
+
   /**
    * find a Cat
    */
@@ -68,6 +90,10 @@ const common_1 = require(\"@nestjs/common\");
 const swagger_1 = require(\"@nestjs/swagger\");
 class Cat {
 }
+class PromiseCat {
+}
+class ObservableCat {
+}
 let AppController = exports.AppController = class AppController {
     onApplicationBootstrap() { }
     /**
@@ -95,6 +121,20 @@ let AppController = exports.AppController = class AppController {
      * @memberof AppController
      */
     async testCreate2() { }
+    /**
+     * create a test PromiseCat
+     *
+     * @returns {Promise<PromiseCat>>}
+     * @memberof AppController
+     */
+    async testCreate3() { }
+    /**
+     * create a test ObservableCat
+     *
+     * @returns {Promise<ObservableCat>}
+     * @memberof AppController
+     */
+    async testCreate4() { }
     /**
      * find a Cat
      */
@@ -122,6 +162,16 @@ __decorate([
     (0, common_1.Post)(),
     openapi.ApiResponse({ status: 201, type: Cat })
 ], AppController.prototype, \"testCreate2\", null);
+__decorate([
+    openapi.ApiOperation({ summary: \"create a test PromiseCat\" }),
+    (0, common_1.Post)(),
+    openapi.ApiResponse({ status: 201, type: PromiseCat })
+], AppController.prototype, \"testCreate3\", null);
+__decorate([
+    openapi.ApiOperation({ summary: \"create a test ObservableCat\" }),
+    (0, common_1.Post)(),
+    openapi.ApiResponse({ status: 201, type: ObservableCat })
+], AppController.prototype, \"testCreate4\", null);
 __decorate([
     (0, swagger_1.ApiOperation)({ summary: \"find a Cat\" }),
     Get(),