diff --git a/.travis.yml b/.travis.yml
index 4b4a9cc..0af48ad 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,5 +12,6 @@ script:
   - git clone https://github.com/herumi/mcl.git
   - cd mcl
   - make test DEBUG=1
+  - make clean
   - make test_go