diff --git a/README.md b/README.md
index 56ca8ac9..874df12f 100644
--- a/README.md
+++ b/README.md
@@ -301,6 +301,14 @@ pnpm run dev
 
 修改 backend/.env.dev 的环境变量 **REDIS_URL**
 
+如需调整前端跨域来源，可在 `backend/.env.dev` 中配置：
+
+```bash
+CORS_ALLOW_ORIGINS=http://localhost:5173,http://127.0.0.1:5173
+```
+
+不建议在需要携带凭据的场景下使用 `CORS_ALLOW_ORIGINS=*`。
+
 配置API Key
 
 1. 使用 WebUI
diff --git a/README_EN.md b/README_EN.md
index cc563098..145adcac 100644
--- a/README_EN.md
+++ b/README_EN.md
@@ -114,6 +114,14 @@ It is recommended to use models with strong capabilities and large parameter cou
 
 Copy `/frontend/.env.example` to `/frontend/.env.development` (remove the `.example` suffix)
 
+If you need to customize allowed frontend origins, set this in `backend/.env.dev`:
+
+```bash
+CORS_ALLOW_ORIGINS=http://localhost:5173,http://127.0.0.1:5173
+```
+
+Avoid `CORS_ALLOW_ORIGINS=*` when requests need credentials.
+
 2. Install Dependencies
 
 Clone the project
diff --git a/backend/app/config/setting.py b/backend/app/config/setting.py
index 897b3cf7..0f5a0914 100644
--- a/backend/app/config/setting.py
+++ b/backend/app/config/setting.py
@@ -10,29 +10,39 @@
 
 class ApiType(str, Enum):
     """LLM API 类型。"""
+
     OPENAI_CHAT = "openai-chat"
     OPENAI_RESPONSES = "openai-responses"
     ANTHROPIC = "anthropic"
 
 
-def parse_cors(value: str) -> list[str]:
-    """将 CORS 配置字符串解析为 URL 列表。
+DEFAULT_CORS_ALLOW_ORIGINS = ["http://localhost:5173", "http://127.0.0.1:5173"]
+
+
+def parse_cors(value: str | list[str]) -> list[str]:
+    """将 CORS 配置解析为 URL 列表。
 
     Args:
-        value: 逗号分隔的 URL 字符串，或 "*" 表示允许所有来源。
+        value: 逗号分隔的 URL 字符串、URL 列表，或 "*" 表示允许所有来源。
 
     Returns:
         解析后的 URL 列表。
     """
+    if isinstance(value, list):
+        return [url.strip() for url in value if url.strip()]
+
+    value = value.strip()
+    if not value:
+        return []
     if value == "*":
         return ["*"]
-    if "," in value:
-        return [url.strip() for url in value.split(",")]
-    return [value]
+
+    return [url.strip() for url in value.split(",") if url.strip()]
 
 
 class Settings(BaseSettings):
     """全局应用配置，从环境变量和 .env 文件加载。"""
+
     ENV: str = "dev"
 
     COORDINATOR_API_TYPE: Optional[ApiType] = None
@@ -70,7 +80,9 @@ class Settings(BaseSettings):
     DEBUG: bool = True
     REDIS_URL: str = "redis://redis:6379/0"
     REDIS_MAX_CONNECTIONS: int = 10
-    CORS_ALLOW_ORIGINS: Annotated[list[str] | str, BeforeValidator(parse_cors)] = "*"
+    CORS_ALLOW_ORIGINS: Annotated[list[str], BeforeValidator(parse_cors)] = (
+        DEFAULT_CORS_ALLOW_ORIGINS
+    )
     SERVER_HOST: str = "http://localhost:8000"
     DEEPSEEK_MODEL: Optional[str] = None
     DEEPSEEK_BASE_URL: Optional[str] = None
diff --git a/backend/app/main.py b/backend/app/main.py
index 8003d08a..5b2180c4 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -8,6 +8,7 @@
 from app.utils.log_util import logger
 from fastapi.staticfiles import StaticFiles
 from app.utils.cli import get_ascii_banner, center_cli_str
+from app.config.setting import settings
 
 
 @asynccontextmanager
@@ -37,10 +38,13 @@ async def lifespan(app: FastAPI):
 
 
 # 跨域 CORS
+cors_allow_origins = settings.CORS_ALLOW_ORIGINS
+cors_allow_credentials = "*" not in cors_allow_origins
+
 app.add_middleware(
     CORSMiddleware,
-    allow_origins=["*"],
-    allow_credentials=True,
+    allow_origins=cors_allow_origins,
+    allow_credentials=cors_allow_credentials,
     allow_methods=["*"],
     allow_headers=["*"],
     expose_headers=["*"],  # 暴露所有响应头