diff --git a/video-gen-api/app/api/v1/sms.py b/video-gen-api/app/api/v1/sms.py
index c53b335c..e842ed4f 100644
--- a/video-gen-api/app/api/v1/sms.py
+++ b/video-gen-api/app/api/v1/sms.py
@@ -1,7 +1,10 @@
-from fastapi import APIRouter, HTTPException, status
+from fastapi import APIRouter, Depends, HTTPException, status
+from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.config import settings
-from app.schemas.sms import SmsSendRequest, SmsVerifyRequest, SmsResponse
+from app.dependencies import get_db
+from app.schemas.sms import SmsResponse, SmsScene, SmsSendRequest, SmsVerifyRequest
+from app.services.auth import get_user_by_phone
 from app.services.sms import generate_and_send_sms, verify_sms_code
 
 router = APIRouter(prefix="/sms", tags=["短信验证码"])
@@ -10,6 +13,7 @@ router = APIRouter(prefix="/sms", tags=["短信验证码"])
 def _validate_captcha_token(captcha_token: str | None) -> None:
     if settings.SMS_MOCK:
         return
+
     if not (req_captcha := captcha_token):
         raise HTTPException(
             status_code=status.HTTP_400_BAD_REQUEST,
@@ -26,15 +30,74 @@ def _validate_captcha_token(captcha_token: str | None) -> None:
         )
 
 
+async def _validate_sms_scene_phone(
+    *,
+    db: AsyncSession,
+    phone: str,
+    scene: SmsScene,
+) -> None:
+    """
+    按短信来源场景做手机号注册状态前置校验。
+
+    规则：
+    1. login：必须是已注册手机号，否则拦截发送。
+    2. register：必须是未注册手机号，否则拦截发送。
+    3. common：通用场景，暂不校验手机号注册状态。
+    4. set_password：保留旧场景，按通用场景处理，暂不校验手机号注册状态。
+    5. 其他未确认场景：理论上会被 SmsScene 枚举拦截；这里额外兜底。
+    """
+    if scene == SmsScene.login:
+        user = await get_user_by_phone(db, phone)
+        if not user:
+            raise HTTPException(
+                status_code=status.HTTP_400_BAD_REQUEST,
+                detail="手机号未注册，请先注册",
+            )
+        return
+
+    if scene == SmsScene.register:
+        user = await get_user_by_phone(db, phone)
+        if user:
+            raise HTTPException(
+                status_code=status.HTTP_400_BAD_REQUEST,
+                detail="该手机号已注册，请直接登录",
+            )
+        return
+
+    if scene in {SmsScene.common, SmsScene.set_password}:
+        return
+
+    raise HTTPException(
+        status_code=status.HTTP_400_BAD_REQUEST,
+        detail="未确认短信场景，禁止发送验证码",
+    )
+
+
 @router.post(
     "/send",
     response_model=SmsResponse,
     summary="发送短信验证码",
-    description="客户端发送短信验证码。scene=register 用于注册，scene=login 用于短信登录，scene=set_password 用于设置密码。正式环境会按配置校验图形验证码。",
+    description=(
+        "客户端发送短信验证码。"
+        "scene=register 用于注册，发送前会校验手机号未注册；"
+        "scene=login 用于短信登录，发送前会校验手机号已注册；"
+        "scene=common 用于通用短信场景，暂不校验手机号注册状态；"
+        "scene=set_password 用于设置密码，保留旧场景，暂按通用场景处理。"
+        "正式环境会按配置校验图形验证码。"
+    ),
 )
-async def send_sms_code(req: SmsSendRequest):
+async def send_sms_code(
+    req: SmsSendRequest,
+    db: AsyncSession = Depends(get_db),
+):
     _validate_captcha_token(req.captcha_token)
 
+    await _validate_sms_scene_phone(
+        db=db,
+        phone=req.phone,
+        scene=req.scene,
+    )
+
     try:
         ok, code = await generate_and_send_sms(req.phone, req.scene.value)
     except ValueError as exc:
@@ -66,4 +129,4 @@ async def verify_sms(req: SmsVerifyRequest):
             status_code=status.HTTP_400_BAD_REQUEST,
             detail="验证码错误或已过期",
         )
-    return SmsResponse(message="验证成功", success=True)
+    return SmsResponse(message="验证成功", success=True)
\ No newline at end of file
diff --git a/video-gen-api/app/schemas/sms.py b/video-gen-api/app/schemas/sms.py
index d070b1f9..1c84396a 100644
--- a/video-gen-api/app/schemas/sms.py
+++ b/video-gen-api/app/schemas/sms.py
@@ -6,21 +6,40 @@ from pydantic import BaseModel, Field
 class SmsScene(str, Enum):
     register = "register"
     login = "login"
+    common = "common"
     set_password = "set_password"
 
 
 class SmsSendRequest(BaseModel):
     phone: str = Field(..., pattern=r"^1[3-9]\d{9}$", description="手机号")
-    scene: SmsScene = Field(..., description="短信场景：register=注册，login=短信登录，set_password=设置密码")
+    scene: SmsScene = Field(
+        ...,
+        description=(
+            "短信场景："
+            "register=注册，"
+            "login=短信登录，"
+            "common=通用场景，"
+            "set_password=设置密码"
+        ),
+    )
     captcha_token: str | None = Field(None, description="图形验证码令牌，正式环境按配置要求传入")
 
 
 class SmsVerifyRequest(BaseModel):
     phone: str = Field(..., pattern=r"^1[3-9]\d{9}$", description="手机号")
-    scene: SmsScene = Field(..., description="短信场景")
+    scene: SmsScene = Field(
+        ...,
+        description=(
+            "短信场景："
+            "register=注册，"
+            "login=短信登录，"
+            "common=通用场景，"
+            "set_password=设置密码"
+        ),
+    )
     code: str = Field(..., min_length=4, max_length=8, description="验证码")
 
 
 class SmsResponse(BaseModel):
     message: str
-    success: bool
+    success: bool
\ No newline at end of file