diff --git a/git-compat-util.h b/git-compat-util.h
index bf9dbe288a..428f171379 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -74,7 +74,11 @@
 #endif
 
 #ifndef PRIuMAX
+#ifndef __MINGW32__
 #define PRIuMAX "llu"
+#else
+#define PRIuMAX "I64u"
+#endif
 #endif
 
 #ifdef __GNUC__