diff --git a/nonebot/plugin/manager.py b/nonebot/plugin/manager.py
index 23597eb1..eb5bef0b 100644
--- a/nonebot/plugin/manager.py
+++ b/nonebot/plugin/manager.py
@@ -10,8 +10,8 @@ from typing import Set, Dict, List, Union, Iterable, Optional, Sequence
 
 from nonebot.log import logger
 from nonebot.utils import escape_tag
-from .plugin import Plugin, _new_plugin
 from . import _managers, _current_plugin
+from .plugin import Plugin, _new_plugin, _confirm_plugin
 
 
 class PluginManager:
@@ -180,6 +180,8 @@ class PluginLoader(SourceFileLoader):
         #     ) from e
         super().exec_module(module)
 
+        _confirm_plugin(plugin)
+
         _current_plugin.reset(_plugin_token)
         return
 
diff --git a/nonebot/plugin/plugin.py b/nonebot/plugin/plugin.py
index 88ebd304..83d37c79 100644
--- a/nonebot/plugin/plugin.py
+++ b/nonebot/plugin/plugin.py
@@ -96,5 +96,10 @@ def _new_plugin(fullname: str, module: ModuleType, manager: "PluginManager") ->
     if name in plugins:
         raise RuntimeError("Plugin already exists! Check your plugin name.")
     plugin = Plugin(name, module, fullname, manager)
-    plugins[name] = plugin
     return plugin
+
+
+def _confirm_plugin(plugin: Plugin) -> None:
+    if plugin.name in plugins:
+        raise RuntimeError("Plugin already exists! Check your plugin name.")
+    plugins[plugin.name] = plugin
diff --git a/tests/test_init.py b/tests/test_init.py
index 46911755..03da1755 100644
--- a/tests/test_init.py
+++ b/tests/test_init.py
@@ -94,3 +94,9 @@ async def test_load_plugin(load_plugin: Set["Plugin"]):
         assert False
     except RuntimeError:
         assert True
+
+    try:
+        nonebot.load_plugin("some_plugin_no_exist")
+        assert False
+    except Exception:
+        assert nonebot.get_plugin("some_plugin_no_exist") is None