diff --git a/tests/bin/start b/tests/bin/start
index b3d73dd..fbdc895 100755
--- a/tests/bin/start
+++ b/tests/bin/start
@@ -5,7 +5,6 @@ set -e
 cd "$(dirname "${BASH_SOURCE[0]}")/../.."
 
 export PYTHONPATH=.ten/app/ten_packages/system/ten_runtime_python/lib:.ten/app/ten_packages/system/ten_runtime_python/interface
-export TEN_DISABLE_ADDON_UNREGISTER_AFTER_APP_CLOSE=true
 
 # If the Python app imports some modules that are compiled with a different
 # version of libstdc++ (ex: PyTorch), the Python app may encounter confusing
diff --git a/tests/conftest.py b/tests/conftest.py
new file mode 100644
index 0000000..27f004f
--- /dev/null
+++ b/tests/conftest.py
@@ -0,0 +1,36 @@
+#
+# Copyright © 2025 Agora
+# This file is part of TEN Framework, an open source project.
+# Licensed under the Apache License, Version 2.0, with certain conditions.
+# Refer to the "LICENSE" file in the root directory for more information.
+#
+import pytest
+import sys
+import os
+from ten import (
+    unregister_all_addons_and_cleanup,
+)
+
+
+@pytest.fixture(scope="session", autouse=True)
+def global_setup_and_teardown():
+    # Set the environment variable.
+    os.environ["TEN_DISABLE_ADDON_UNREGISTER_AFTER_APP_CLOSE"] = "true"
+
+    # Verify the environment variable is correctly set.
+    if (
+        "TEN_DISABLE_ADDON_UNREGISTER_AFTER_APP_CLOSE" not in os.environ
+        or os.environ["TEN_DISABLE_ADDON_UNREGISTER_AFTER_APP_CLOSE"] != "true"
+    ):
+        print(
+            "Failed to set TEN_DISABLE_ADDON_UNREGISTER_AFTER_APP_CLOSE",
+            file=sys.stderr,
+        )
+        sys.exit(1)
+
+    # Yield control to the test; after the test execution is complete, continue
+    # with the teardown process.
+    yield
+
+    # Teardown part.
+    unregister_all_addons_and_cleanup()