diff --git a/types/mongodb/index.d.ts b/types/mongodb/index.d.ts
index 8b5a637ebd..00356214c6 100644
--- a/types/mongodb/index.d.ts
+++ b/types/mongodb/index.d.ts
@@ -97,6 +97,10 @@ export interface MongoClientOptions extends
     validateOptions?: Object;
     // The name of the application that created this MongoClient instance.
     appname?: string;
+    auth?: {
+        user: string;
+        password: string;
+    }
 }
 
 export interface SSLOptions {