diff --git a/nonebot_plugin_llmchat/__init__.py b/nonebot_plugin_llmchat/__init__.py
index 5903779..d953d5c 100644
--- a/nonebot_plugin_llmchat/__init__.py
+++ b/nonebot_plugin_llmchat/__init__.py
@@ -204,7 +204,7 @@ async def process_messages(group_id: int):
     preset = get_preset(group_id)
 
     # 初始化OpenAI客户端
-    if preset.proxy:
+    if preset.proxy != "":
         client = AsyncOpenAI(
             base_url=preset.api_base,
             api_key=preset.api_key,
diff --git a/nonebot_plugin_llmchat/config.py b/nonebot_plugin_llmchat/config.py
index 6b02ac2..3de419e 100644
--- a/nonebot_plugin_llmchat/config.py
+++ b/nonebot_plugin_llmchat/config.py
@@ -10,7 +10,7 @@ class PresetConfig(BaseModel):
     model_name: str = Field(..., description="模型名称")
     max_tokens: int = Field(2048, description="最大响应token数")
     temperature: float = Field(0.7, description="生成温度（0-2]")
-    proxy = Field(None, description="HTTP代理服务器")
+    proxy: str = Field("", description="HTTP代理服务器")
 
 
 class ScopedConfig(BaseModel):