diff --git a/src/util/detect_os.h b/src/util/detect_os.h
index 86286dfbe70..74037240c74 100644
--- a/src/util/detect_os.h
+++ b/src/util/detect_os.h
@@ -72,7 +72,7 @@
 #define DETECT_OS_POSIX 1
 #endif
 
-#if defined(_WIN32) || defined(WIN32)
+#if defined(_WIN32)
 #define DETECT_OS_WINDOWS 1
 #endif