diff --git a/tests/cores/mega/test_aio.py b/tests/cores/mega/test_aio.py
index 4187cb0349..cc9bd5652a 100644
--- a/tests/cores/mega/test_aio.py
+++ b/tests/cores/mega/test_aio.py
@@ -81,7 +81,7 @@ def tearDown(self):
         self.process3.terminate()
 
     async def test_schedule(self):
-        t = time.time()
+        t = time.monotonic()
         task1 = asyncio.create_task(self.service_builder.schedule(initial_inputs={"text": "hello, "}))
         task2 = asyncio.create_task(self.service_builder.schedule(initial_inputs={"text": "hi, "}))
         await asyncio.gather(task1, task2)
@@ -93,7 +93,7 @@ async def test_schedule(self):
         self.assertEqual(result_dict2[self.s2.name]["text"], "hi, opea project1!")
         self.assertEqual(result_dict2[self.s3.name]["text"], "hi, opea project2!")
         self.assertEqual(len(self.service_builder.get_all_final_outputs(result_dict1, runtime_graph1).keys()), 2)
-        self.assertEqual(int(time.time() - t), 15)
+        self.assertEqual(int(time.monotonic() - t), 15)
 
 
 if __name__ == "__main__":
diff --git a/tests/cores/mega/test_service_orchestrator_streaming.py b/tests/cores/mega/test_service_orchestrator_streaming.py
index 1327a59344..b3199ad712 100644
--- a/tests/cores/mega/test_service_orchestrator_streaming.py
+++ b/tests/cores/mega/test_service_orchestrator_streaming.py
@@ -112,7 +112,7 @@ def test_extract_chunk_str(self):
         self.assertEqual(res, "example test.")
 
     def test_token_generator(self):
-        start = time.time()
+        start = time.monotonic()
         sentence = "I write an example test.</s>"
         for i in self.service_builder.token_generator(
             sentence=sentence, token_start=start, is_first=True, is_last=False