diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 6deee06..e23363b 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -14,7 +14,7 @@ jobs:
 
     strategy:
       matrix:
-        os: [windows-2016, macos-latest, ubuntu-18.04]
+        os: [windows-2016, macos-latest, ubuntu-16.04]
 
     steps:
       - uses: actions/checkout@v2