diff --git a/lib/common/helper.js b/lib/common/helper.js
index 91bfeb3..9500ed5 100644
--- a/lib/common/helper.js
+++ b/lib/common/helper.js
@@ -32,24 +32,27 @@ _.exec = function(cmd, opts) {
 
 _.spawn = function() {
   var args = Array.prototype.slice.call(arguments);
-  return new Promise(function(resolve, reject) {
+  return new Promise((resolve, reject) => {
     var stdout = '';
     var stderr = '';
     var child = childProcess.spawn.apply(childProcess, args);
 
-    child.on('error', function(error) {
+    child.stdout.setEncoding('utf8');
+    child.stderr.setEncoding('utf8');
+
+    child.on('error', error => {
       reject(error);
     });
 
-    child.stdout.on('data', function(data) {
+    child.stdout.on('data', data => {
       stdout += data;
     });
 
-    child.stderr.on('data', function(data) {
+    child.stderr.on('data', data => {
       stderr += data;
     });
 
-    child.on('close', function(code) {
+    child.on('close', code => {
       var error;
       if (code) {
         error = new Error(stderr);
diff --git a/package.json b/package.json
index 8a31fc5..0b02b12 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "macaca-client",
-  "version": "1.0.9",
+  "version": "1.0.10",
   "description": "macaca client for automation",
   "keywords": [
     "automation",