diff --git a/ports/zlib/portfile.cmake b/ports/zlib/portfile.cmake
index 6deff6c0c..81d54fb4b 100644
--- a/ports/zlib/portfile.cmake
+++ b/ports/zlib/portfile.cmake
@@ -2,7 +2,7 @@ include(vcpkg_common_functions)
 set(SOURCE_PATH ${CURRENT_BUILDTREES_DIR}/src/zlib-1.2.10)
 vcpkg_download_distfile(ARCHIVE_FILE
     URLS "http://www.zlib.net/zlib-1.2.10.tar.gz"
-    FILENAME "zlib1210.zip"
+    FILENAME "zlib1210.tar.gz"
     SHA512 5fa71052a418a0f2b345fce28af9941bbd1c6ee276ce506ab3092157f15776ee41f96bb1799657227513b852913f96ac52dae8122a437f34b43933ee48d63ee0
 )
 vcpkg_extract_source_archive(${ARCHIVE_FILE})