diff --git a/Makefile b/Makefile
index a59b5ca..1245ed1 100644
--- a/Makefile
+++ b/Makefile
@@ -105,7 +105,7 @@ $(BUILD):
 #-------------------------------------------------------------------------------
 clean:
 	@echo clean ...
-	@rm -fr $(BUILD) $(TARGET).wps $(TARGET).elf
+	@rm -fr $(BUILD)/* $(TARGET).wps $(TARGET).elf
 
 #-------------------------------------------------------------------------------
 else