diff --git a/app/api/routers/rbac_compute_pricing.py b/app/api/routers/rbac_compute_pricing.py
index 0af898a..485ce15 100644
--- a/app/api/routers/rbac_compute_pricing.py
+++ b/app/api/routers/rbac_compute_pricing.py
@@ -1020,7 +1020,9 @@ async def transfer_from_personal(
         raise HTTPException(status_code=500, detail="个人算力账号未就绪")
     total_micro = amount_fen * MICRO_PER_FEN
 
-    # ★ 服务端严格校验个人可用余额（以平台账本为权威，引擎余额为参考）
+    # ★ 个人可转余额以引擎可用额度为权威（quota - used_quota，即个人实际可消费的算力）。
+    #   平台账本 compute_personal_balance 仅记录「个人充值/企业转入」的累计，可能与引擎额度
+    #   不一致（赠送/历史调整等），转账时同步扣减、不足扣到 0、不转负。
     from ..infrastructure.models import User as _User
     from sqlalchemy import update as _sa_update
     user_row = await db.session.get(_User, user["id"])
@@ -1030,34 +1032,30 @@ async def transfer_from_personal(
         quota_micro = int(user_bal.get("quota", 0) or 0)
         used_micro = int(user_bal.get("used_quota", 0) or 0)
         available_micro = max(0, quota_micro - used_micro)
-    except Exception as exc:
-        raise HTTPException(status_code=502, detail=f"查询个人余额失败: {exc}") from exc
-    if ledger_balance < amount_fen:
-        raise HTTPException(
-            status_code=400,
-            detail=f"个人可转余额不足：账本可用 ¥{ledger_balance / 100:.2f}，尝试转出 ¥{body.amount_yuan:.2f}",
-        )
+    except Exception as exc:  # noqa: BLE001
+        raise HTTPException(status_code=502, detail="查询个人余额失败，请稍后重试") from exc
     if available_micro < total_micro:
         raise HTTPException(
             status_code=400,
-            detail=f"个人可用余额不足：可用 ¥{available_micro / 1000000:.2f}，尝试转出 ¥{body.amount_yuan:.2f}",
+            detail=f"个人可用余额不足：可用 ¥{available_micro / 1000000:.2f}，本次需转出 ¥{body.amount_yuan:.2f}",
         )
 
-    # 先扣账本（幂等条件更新，防止并发超扣）
-    upd = await db.session.execute(
-        _sa_update(_User)
-        .where(_User.id == user["id"], _User.compute_personal_balance >= amount_fen)
-        .values(compute_personal_balance=_User.compute_personal_balance - amount_fen)
-    )
-    if upd.rowcount == 0:
-        raise HTTPException(status_code=400, detail="个人可转余额不足（账本校验失败）")
-
+    # 先扣引擎额度（引擎为权威），成功后再落库
     try:
         await compute_client.adjust_user_quota(engine_user_id, total_micro, "subtract")
-    except Exception as exc:
-        raise HTTPException(status_code=400, detail=f"个人余额扣减失败: {exc}") from exc
+    except Exception as exc:  # noqa: BLE001
+        raise HTTPException(status_code=400, detail="个人余额扣减失败，请稍后重试") from exc
     await compute_client.sync_user_mirror(db, engine_user_id)
 
+    # 账本同步扣减（不足扣到 0，不转负）
+    new_ledger = max(0, ledger_balance - amount_fen)
+    if new_ledger != ledger_balance:
+        await db.session.execute(
+            _sa_update(_User)
+            .where(_User.id == user["id"])
+            .values(compute_personal_balance=new_ledger)
+        )
+
     # 增加企业余额
     company.compute_balance = (company.compute_balance or 0) + amount_fen