diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 89fa0ce1c7..29cd340b9f 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -63,19 +63,19 @@ jobs:
           - CC: gcc
             feature_set: max
             arch: i386
-            os: ubuntu-16.04
+            os: ubuntu-18.04
             name_extra: for 32-bit arch (legacy OS)
 
           - CC: g++
             feature_set: max
             arch: i386
-            os: ubuntu-16.04
+            os: ubuntu-18.04
             name_extra: for 32-bit arch (legacy OS)
 
           - CC: clang
             feature_set: max
             arch: i386
-            os: ubuntu-16.04
+            os: ubuntu-18.04
             name_extra: for 32-bit arch (legacy OS)
 
     name: ${{ matrix.feature_set }} features with ${{ matrix.CC }} ${{ matrix.name_extra }}