diff --git a/winml/test/common/googleTestMacros.h b/winml/test/common/googleTestMacros.h
index dc38c6402f..f0507435b9 100644
--- a/winml/test/common/googleTestMacros.h
+++ b/winml/test/common/googleTestMacros.h
@@ -10,18 +10,20 @@
   }
 
 #define WINML_TEST_CLASS_BEGIN_NO_SETUP(test_class_name) \
-  class test_class_name : public ::testing::Test {       \
-  };
+  namespace {                                            \
+    class test_class_name : public ::testing::Test {     \
+    };
 
 #define WINML_TEST_CLASS_BEGIN_WITH_SETUP(test_class_name, setup_method) \
-  class test_class_name : public ::testing::Test {                       \
-   protected:                                                            \
-    void SetUp() override {                                              \
-      getapi().setup_method();                                           \
-    }                                                                    \
-  };
+  namespace {                                                            \
+    class test_class_name : public ::testing::Test {                     \
+    protected:                                                           \
+      void SetUp() override {                                            \
+        getapi().setup_method();                                         \
+      }                                                                  \
+    };
 
-#define WINML_TEST_CLASS_END()
+#define WINML_TEST_CLASS_END() }
 
 // For old versions of gtest without GTEST_SKIP, stream the message and return success instead
 #ifndef GTEST_SKIP
@@ -77,4 +79,4 @@
   if (auto isEdgeCore = RuntimeParameters::Parameters.find("EdgeCore");                 \
       isEdgeCore != RuntimeParameters::Parameters.end() && isEdgeCore->second != "0") { \
     WINML_SKIP_TEST("Test can't be run in EdgeCore");                                   \
-  }
\ No newline at end of file
+  }