diff --git a/index.js b/index.js
index aacf6ef..538e440 100644
--- a/index.js
+++ b/index.js
@@ -66,8 +66,7 @@ function co(gen) {
       } catch (e) {
         return reject(e);
       }
-      next(ret);
-      return null;
+      return next(ret);
     }
 
     /**