diff --git a/make/defs.mk b/make/defs.mk
index 8e0f91a8..ec9fea09 100644
--- a/make/defs.mk
+++ b/make/defs.mk
@@ -233,8 +233,8 @@ ifeq ($(TARGET),mingw)
   CROSS_TOOL_DIR      ?=
   CROSS_TOOL_BIN_PREFIX ?= $(CROSS_TOOL_DIR)/usr/bin/i686-w64-mingw32-
   PROJECT_LDFLAGS     += -L$(MINGW_SYS_ROOT)/lib
-  PROJECT_CFLAGS      += -L$(MINGW_SYS_ROOT)/include
-  PROJECT_CPPFLAGS    += -L$(MINGW_SYS_ROOT)/include
+  PROJECT_CFLAGS      += -I$(MINGW_SYS_ROOT)/include
+  PROJECT_CPPFLAGS    += -I$(MINGW_SYS_ROOT)/include
  else
   CROSS_TOOL_DIR      ?= /opt/cross-tools
   CROSS_TOOL_BIN_PREFIX ?= $(CROSS_TOOL_DIR)/bin/i686-pc-mingw32-