diff --git a/.travis.yml b/.travis.yml
index 66d002f9a40..208084bf95b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,8 +5,8 @@ python:
   - 3.4
   - 3.5
 install:
-  - python3 setup.py -q develop
-  - script/gen_requirements_all.py validate
+  # Validate requirements_all.txt on Python 3.5
+  - if [[ $TRAVIS_PYTHON_VERSION == '3.5' ]]; then python3 setup.py -q develop; script/gen_requirements_all.py validate; fi
   - script/bootstrap_server
 script:
   - script/cibuild