diff --git a/types/multer/index.d.ts b/types/multer/index.d.ts
index fb9bee6c0d..f056323625 100644
--- a/types/multer/index.d.ts
+++ b/types/multer/index.d.ts
@@ -43,7 +43,7 @@ declare namespace multer {
             preservePath?: boolean;
         };
         /** A function to control which files to upload and which to skip. */
-        fileFilter?(req: Express.Request, file: Express.Multer.File, callback: (error: Error, acceptFile: boolean) => void): void;
+        fileFilter?(req: Express.Request, file: Express.Multer.File, callback: (error: Error | null, acceptFile: boolean) => void): void;
     }
 
     interface StorageEngine {
diff --git a/types/multer/multer-tests.ts b/types/multer/multer-tests.ts
index e5af7862d5..49d8ccc182 100644
--- a/types/multer/multer-tests.ts
+++ b/types/multer/multer-tests.ts
@@ -1,7 +1,12 @@
 import * as express from 'express';
 import * as multer from 'multer';
 
-const upload = multer({ dest: 'uploads/' });
+const upload = multer({
+    dest: 'uploads/',
+    fileFilter: (req, file, cb) => {
+        cb(null, true);
+    }
+});
 
 const app = express();