diff --git a/dlls/comctl32/comctl32.spec b/dlls/comctl32/comctl32.spec
index 2e02e9d..2e4c2b5 100644
--- a/dlls/comctl32/comctl32.spec
+++ b/dlls/comctl32/comctl32.spec
@@ -169,7 +169,7 @@
 362 stdcall StrStrW(wstr wstr) COMCTL32_StrStrW
 363 stub StrStrIW
 364 stdcall StrSpnW(wstr wstr) COMCTL32_StrSpnW
-365 stub StrToIntW
+365 stdcall StrToIntW(wstr) COMCTL32_StrToIntW
 366 stub StrChrIA
 367 stub StrChrIW
 368 stub StrRChrIA
diff --git a/dlls/comctl32/comctl32undoc.c b/dlls/comctl32/comctl32undoc.c
index d6aee22..25758fa 100644
--- a/dlls/comctl32/comctl32undoc.c
+++ b/dlls/comctl32/comctl32undoc.c
@@ -48,6 +48,7 @@
 
 typedef HRESULT CALLBACK (*DPALOADPROC)(LPLOADDATA,IStream*,LPARAM);
 
+INT __cdecl _wtoi(LPWSTR string);
 
 /**************************************************************************
  * DPA_LoadStream [COMCTL32.9]
@@ -2080,6 +2081,16 @@
     return atoi(lpString);
 }
 
+/**************************************************************************
+ * StrToIntW [COMCTL32.365] Converts a wide char string to a signed integer.
+ */
+
+INT WINAPI
+COMCTL32_StrToIntW (LPWSTR lpString)
+{
+    return _wtoi(lpString);
+}
+
 
 /**************************************************************************
  * DPA_EnumCallback [COMCTL32.385]