diff --git a/cocos/2d/ccUTF8.cpp b/cocos/2d/ccUTF8.cpp
index 6e70a313d5..c4b9893a04 100644
--- a/cocos/2d/ccUTF8.cpp
+++ b/cocos/2d/ccUTF8.cpp
@@ -279,7 +279,7 @@ cc_utf8_get_char (const char * p)
 
 unsigned short* cc_utf8_to_utf16(const char* str_old, int length/* = -1 */, int* rUtf16Size/* = nullptr */)
 {
-    unsigned short len = cc_utf8_strlen(str_old, length);
+    long len = cc_utf8_strlen(str_old, length);
     if (rUtf16Size != nullptr) {
         *rUtf16Size = len;
     }