diff --git a/.travis.yml b/.travis.yml
index fe923dee..7c55d592 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,6 +2,7 @@ language: php
 dist: trusty
 
 php:
+  - 5.6
   - 7.0
   - 7.1
   - 7.2