diff --git a/index.js b/index.js
index 258ceec..d85c4ec 100644
--- a/index.js
+++ b/index.js
@@ -13,6 +13,7 @@ module.exports = function(o_params){
 		allowNotice: true,
 		pull: (params, callback, err_callback) => pull(params, callback, err_callback),
 		push: (params, callback) => push(params, callback),
+		diff: (callback) => diff(callback),
 		sync: (callback, err_callback, params_pull, params_push) => sync(callback, err_callback, params_pull, params_push),
 		schedule: (time, callback, err_callback, params_pull, params_push) => schedule(time, callback, err_callback, params_pull, params_push)
 	}
@@ -103,6 +104,11 @@ module.exports = function(o_params){
    			});
 	}
 
+	/* check diff */
+	var diff = function(callback){
+		git.diffSummary(callback);
+	}
+
 	/* sync action */
 	var sync = function(callback, err_callback, params_pull, params_push){
 		pull(params_pull, callback, err_callback);
diff --git a/test-diff.js b/test-diff.js
new file mode 100644
index 0000000..f295148
--- /dev/null
+++ b/test-diff.js
@@ -0,0 +1,5 @@
+const crongit = require('./index.js')();
+
+//crongit.pull({}, ()=>{console.log('good')}, ()=>{console.log('bed')});
+//crongit.schedule("*/10 * * * * *", ()=>console.log('test ok!!!\nuse Ctrl+C to exit!!'), ()=>console.log('pull err err err err!!!!'));
+crongit.diff(function(d,err){console.log(err)});