diff --git a/appveyor.yml b/appveyor.yml
index ad42cff..61f4fdd 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -12,7 +12,7 @@ build_script:
 
     set SDL_VER=2.0.9
 
-    set ZLIB_VER=1.2.13
+    set ZLIB_VER=1.3
 
     echo === Environment ====================================================