diff --git a/QGCExternalLibs.pri b/QGCExternalLibs.pri
index 021fe9cb481012b94be3edbba10b306a0d6a4a9e..f587f4ac3893ad21bd96275d7470c037c4b29c95 100644
--- a/QGCExternalLibs.pri
+++ b/QGCExternalLibs.pri
@@ -110,7 +110,7 @@ SOURCES += \
 
 #
 # [REQUIRED] zlib library
-Windows {
+WindowsBuild {
     INCLUDEPATH +=  $$SOURCE_DIR/libs/zlib/windows/include
     LIBS += -L$$SOURCE_DIR/libs/zlib/windows/lib
 }