diff --git a/Installation/include/CGAL/config.h b/Installation/include/CGAL/config.h
index bb9314151fa..d5ada62628c 100644
--- a/Installation/include/CGAL/config.h
+++ b/Installation/include/CGAL/config.h
@@ -146,7 +146,7 @@ namespace CGAL {
    || defined(__x86_64) || defined(__x86_64__) \
    || defined(__ia64) || defined(__ia64__) \
    || defined(_M_IX86) || defined(_M_IA64) \
-   || defined(_M_ALPHA)
+   || defined(_M_ALPHA) || defined(_WIN64)
 #  define CGAL_LITTLE_ENDIAN
 #else
 #  error Unknown endianness