diff --git a/packages/okam-build/lib/processor/js/polyfill/async.js b/packages/okam-build/lib/processor/js/polyfill/async.js
index 0cad0eea..c220dc18 100644
--- a/packages/okam-build/lib/processor/js/polyfill/async.js
+++ b/packages/okam-build/lib/processor/js/polyfill/async.js
@@ -20,6 +20,32 @@ module.exports = function ({types: t}) {
              */
             AwaitExpression(path, state) {
                 importLocalPolyfill(false, path, state, t);
+            },
+
+            /**
+             * Process `async xxx` expression
+             *
+             * @param {Object} path the node path
+             * @param {Object} state the plugin state
+             */
+            FunctionExpression(path, state) {
+                let node = path.node;
+                if (node.async) {
+                    importLocalPolyfill(false, path, state, t);
+                }
+            },
+
+            /**
+             * Process `async xxx() {}` object member
+             *
+             * @param {Object} path the node path
+             * @param {Object} state the plugin state
+             */
+            ObjectMember(path, state) {
+                let node = path.node;
+                if (node.async) {
+                    importLocalPolyfill(false, path, state, t);
+                }
             }
         }
     };
diff --git a/packages/okam-build/lib/processor/js/polyfill/helper.js b/packages/okam-build/lib/processor/js/polyfill/helper.js
index 06a22ec8..ce91e34b 100644
--- a/packages/okam-build/lib/processor/js/polyfill/helper.js
+++ b/packages/okam-build/lib/processor/js/polyfill/helper.js
@@ -43,6 +43,7 @@ exports.importLocalPolyfill = function (name, path, state, t) {
     if (name === false) {
         name = importName;
     }
+
     if (!shouldPolyfill(importName, name, path)) {
         return;
     }