diff --git a/reactos/include/reactos/libs/mbedtls/config.h b/reactos/include/reactos/libs/mbedtls/config.h
index a6d950f48b3..d413e99647a 100644
--- a/reactos/include/reactos/libs/mbedtls/config.h
+++ b/reactos/include/reactos/libs/mbedtls/config.h
@@ -29,9 +29,11 @@
 #ifndef MBEDTLS_CONFIG_H
 #define MBEDTLS_CONFIG_H
 
+#ifndef __REACTOS__
 #if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_DEPRECATE)
 #define _CRT_SECURE_NO_DEPRECATE 1
 #endif
+#endif
 
 /**
  * \name SECTION: System support