diff --git a/docs/source/viztracer.rst b/docs/source/viztracer.rst
index 222f1265..1cc4cf22 100644
--- a/docs/source/viztracer.rst
+++ b/docs/source/viztracer.rst
@@ -29,7 +29,7 @@ VizTracer
                  sanitize_function_name=False,\
                  process_name=None,\
                  output_file="result.json",\
-                 plugins=[])
+                 plugins=None)
 
     .. py:attribute:: tracer_entries
         :type: int
@@ -339,8 +339,8 @@ VizTracer
             viztracer -o <filepath>
 
     .. py:attribute:: plugins
-        :type: Sequence[Union[VizPluginBase, str]]
-        :value: []
+        :type: Optional[Sequence[Union[VizPluginBase, str]]]
+        :value: None
 
         List of plugins to use.
     
diff --git a/src/viztracer/vizplugin.py b/src/viztracer/vizplugin.py
index ff9f3b64..9a82700e 100644
--- a/src/viztracer/vizplugin.py
+++ b/src/viztracer/vizplugin.py
@@ -51,23 +51,24 @@ def message(self, m_type: str, payload: dict) -> dict:
 
 
 class VizPluginManager:
-    def __init__(self, tracer: "VizTracer", plugins: Sequence[Union[VizPluginBase, str]]):
+    def __init__(self, tracer: "VizTracer", plugins: Optional[Sequence[Union[VizPluginBase, str]]]):
         self._tracer = tracer
         self._plugins = []
-        for plugin in plugins:
-            if isinstance(plugin, VizPluginBase):
-                plugin_instance = plugin
-            elif isinstance(plugin, str):
-                plugin_instance = self._get_plugin_from_string(plugin)
-            else:
-                raise TypeError("Invalid plugin!")
-            self._plugins.append(plugin_instance)
-
-            support_version = plugin_instance.support_version()
-            if compare_version(support_version, __version__) > 0:
-                color_print("WARNING", "The plugin support version is higher than "
-                                       "viztracer version. Consider update your viztracer")
-            self._send_message(plugin_instance, "event", {"when": "initialize"})
+        if plugins:
+            for plugin in plugins:
+                if isinstance(plugin, VizPluginBase):
+                    plugin_instance = plugin
+                elif isinstance(plugin, str):
+                    plugin_instance = self._get_plugin_from_string(plugin)
+                else:
+                    raise TypeError("Invalid plugin!")
+                self._plugins.append(plugin_instance)
+
+                support_version = plugin_instance.support_version()
+                if compare_version(support_version, __version__) > 0:
+                    color_print("WARNING", "The plugin support version is higher than "
+                                           "viztracer version. Consider update your viztracer")
+                self._send_message(plugin_instance, "event", {"when": "initialize"})
 
     def _get_plugin_from_string(self, plugin: str) -> VizPluginBase:
         args = plugin.split()
diff --git a/src/viztracer/viztracer.py b/src/viztracer/viztracer.py
index 28bc506e..06972e26 100644
--- a/src/viztracer/viztracer.py
+++ b/src/viztracer/viztracer.py
@@ -51,7 +51,7 @@ def __init__(self,
                  sanitize_function_name: bool = False,
                  process_name: Optional[str] = None,
                  output_file: str = "result.json",
-                 plugins: Sequence[Union[VizPluginBase, str]] = []) -> None:
+                 plugins: Optional[Sequence[Union[VizPluginBase, str]]] = None) -> None:
         super().__init__(tracer_entries)
 
         # Members of C Tracer object