diff --git a/app/api/mobile/api.rb b/app/api/mobile/api.rb
index f3f0cf935..c86a36d05 100644
--- a/app/api/mobile/api.rb
+++ b/app/api/mobile/api.rb
@@ -1,3 +1,5 @@
+#coding=utf-8
+
 module Mobile
   require_relative 'middleware/error_handler'
   require_relative 'apis/auth'