diff --git a/contrib/unzip/ioapi.c b/contrib/unzip/ioapi.c
index 582857d22..44a9e11a3 100644
--- a/contrib/unzip/ioapi.c
+++ b/contrib/unzip/ioapi.c
@@ -10,7 +10,11 @@
 #include <stdlib.h>
 #include <string.h>
 
-#include "../../contrib/zlib/zlib.h"
+#	ifdef ASSIMP_BUILD_NO_OWN_ZLIB
+#		include <zlib.h>
+#	else
+#		include "../zlib/zlib.h"
+#	endif
 #include "ioapi.h"