diff --git a/ucloud/docs/Makefile b/ucloud/docs/Makefile
index a62df24..5e7ea85 100644
--- a/ucloud/docs/Makefile
+++ b/ucloud/docs/Makefile
@@ -20,3 +20,6 @@ permissions: build
 
 build:
 	$(SPHINXBUILD) "$(SOURCEDIR)" "$(BUILDDIR)"
+
+clean:
+	rm -rf $(BUILDDIR)