diff --git a/.github/workflows/unit_tests_ci.yml b/.github/workflows/unit_tests_ci.yml
index b3d65eb91..cbae2783a 100644
--- a/.github/workflows/unit_tests_ci.yml
+++ b/.github/workflows/unit_tests_ci.yml
@@ -32,7 +32,6 @@ jobs:
             python_version: '3.10'
           - tf_version: '1.15.5'
             python_version: '3.7'
-            os: 'ubuntu-latest'
             opset_version: '15'
             ort_version: '1.14.1'
             onnx_version: '1.14.1'