diff --git a/app/admin/controller/system/Host.php b/app/admin/controller/system/Host.php
index 33fcf47..22695a5 100644
--- a/app/admin/controller/system/Host.php
+++ b/app/admin/controller/system/Host.php
@@ -10,4 +10,13 @@ use base\admin\controller\system\HostBase;
  */
 class Host extends HostBase
 {
+    /**
+     * 设置主节点.
+     *
+     * @\app\admin\service\annotation\NodeAnotation(title="设置主节点")
+     */
+    public function setMaster()
+    {
+        return parent::setMaster();
+    }
 }
diff --git a/extend/base/common/service/HostServiceBase.php b/extend/base/common/service/HostServiceBase.php
index 30f3f54..67be5ad 100644
--- a/extend/base/common/service/HostServiceBase.php
+++ b/extend/base/common/service/HostServiceBase.php
@@ -79,6 +79,8 @@ class HostServiceBase
             // 主节点自动选举：若无在线主节点，当前节点自动成为主节点
             $master = SystemHost::where('is_master', 1)->where('status', 1)->find();
             if (empty($master)) {
+                // 先清除所有旧的主节点标记（含已离线的），避免出现多个 is_master=1
+                SystemHost::where('is_master', 1)->update(['is_master' => 0]);
                 $host->is_master = 1;
                 $host->save();
                 Log::info("节点 [{$nodeId}] 自动当选为主节点。");