diff --git a/src/db.rs b/src/db.rs
index 533a6ce..ddb7ab9 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -615,6 +615,12 @@ pub async fn confirm_payment_order(
     // 发送支付成功通知
     let _ = insert_payment_notification(pool, user_id, order_no).await;
 
+    // 验证会员到期时间是否正常
+    if let Err(e) = verify_membership_after_payment(pool, order_no).await {
+        tracing::warn!("会员到期时间验证异常 (订单 {}): {}", order_no, e);
+        
+    }
+
     Ok(new_expires)
 }
 
@@ -685,6 +691,11 @@ pub async fn confirm_payment_order_by_orderno(
         let _ = insert_payment_audit_log(pool, order_no, uid, "paid", None, None).await;
         // 发送支付成功通知
         let _ = insert_payment_notification(pool, uid, order_no).await;
+
+        // 验证会员到期时间是否正常
+        if let Err(e) = verify_membership_after_payment(pool, order_no).await {
+            tracing::warn!("会员到期时间验证异常 (订单 {}): {}", order_no, e);
+            }
     }
 
     Ok(())
@@ -1046,6 +1057,11 @@ pub async fn admin_force_confirm_order(
         )
         .await;
 
+        // 验证会员到期时间是否正常
+        if let Err(e) = verify_membership_after_payment(pool, order_no).await {
+            tracing::warn!("会员到期时间验证异常 (订单 {}): {}", order_no, e);
+            }
+
         result
     } else {
         // 订单已处理，只写日志
@@ -1185,3 +1201,64 @@ pub async fn admin_refund_order(
 
     Ok(())
 }
+
+
+/// 支付确认后验证会员到期时间是否正常
+/// 用于捕获 ELSE INTERVAL '0 days' 的静默错误
+async fn verify_membership_after_payment(
+    pool: &PgPool,
+    order_no: &str,
+) -> Result<(), AppError> {
+    #[derive(Debug, sqlx::FromRow)]
+    struct PaymentResult {
+        package_type: String,
+        paid_at: chrono::DateTime<chrono::Utc>,
+        membership_expires_at: Option<chrono::DateTime<chrono::Utc>>,
+    }
+
+    let row = sqlx::query_as::<_, PaymentResult>(
+        r#"
+        SELECT po.package_type, po.paid_at, u.membership_expires_at
+        FROM payment_orders po
+        JOIN users u ON u.id = po.user_id
+        WHERE po.order_no = $1
+        "#,
+    )
+    .bind(order_no)
+    .fetch_optional(pool)
+    .await
+    .map_err(|e| AppError::Database(format!("验证查询失败: {}", e)))?;
+
+    let r = match row {
+        Some(r) => r,
+        None => return Err(AppError::NotFound("验证查询：订单不存在".to_string())),
+    };
+
+    if r.package_type == "permanent" {
+        return Ok(());  // 永久会员不累计
+    }
+
+    let expires = match r.membership_expires_at {
+        Some(e) => e,
+        None => {
+            let msg = format!("支付验证失败：{} 非永久套餐但会员到期为 NULL", r.package_type);
+            tracing::error!("{}", msg);
+            return Err(AppError::Internal(msg));
+        }
+    };
+
+    let actual_days = (expires - r.paid_at).num_days();
+
+    // 预期至少 25 天（最短月卡 30 天，允许 5 天误差）
+    if actual_days < 25 {
+        let msg = format!(
+            "支付验证失败：套餐 {} 仅增加 {} 天会员时长（预期 >= 25 天），可能触发了 ELSE 分支",
+            r.package_type, actual_days
+        );
+        tracing::error!("{}", msg);
+        return Err(AppError::Internal(msg));
+    }
+
+    tracing::info!("支付验证通过：{} 增加 {} 天", r.package_type, actual_days);
+    Ok(())
+}