diff --git a/src/VkBootstrap.cpp b/src/VkBootstrap.cpp
index 8ca3a88..39a683f 100644
--- a/src/VkBootstrap.cpp
+++ b/src/VkBootstrap.cpp
@@ -21,7 +21,9 @@
 
 #if defined(_WIN32)
 #include <fcntl.h>
+#ifndef NOMINMAX
 #define NOMINMAX
+#endif
 #include <windows.h>
 #endif // _WIN32