diff --git a/ShadowsocksX-NG2/App/ProxyRuntimeController+SystemProxyGate.swift b/ShadowsocksX-NG2/App/ProxyRuntimeController+SystemProxyGate.swift
index 9b065dcc..f8638b7b 100644
--- a/ShadowsocksX-NG2/App/ProxyRuntimeController+SystemProxyGate.swift
+++ b/ShadowsocksX-NG2/App/ProxyRuntimeController+SystemProxyGate.swift
@@ -142,16 +142,31 @@ extension ProxyRuntimeController {
     }
   }
 
-  /// helper 可用性门禁（issue #71）：已批准即通过；未注册则尝试注册（注册
-  /// 本身不弹授权框）；待批准或注册失败时置位批准路径并保持待应用。
+  /// helper 可用性门禁（issue #71）：已批准即通过——仅当 LaunchDaemon 清单
+  /// 与上次注册时的指纹漂移（app 更新改过清单）才注销重注刷新 launchd 的
+  /// job 定义；未注册则尝试注册（注册本身不弹授权框，成功即记指纹）；待批准
+  /// 或注册失败时置位批准路径并保持待应用。
   private func ensureHelperAvailableForApply() -> Bool {
     switch systemProxyHelper.status {
     case .approved:
-      systemProxyApprovalRequired = false
-      return true
+      if Self.helperRegistrationDrifted() {
+        do {
+          try systemProxyHelper.unregister()
+          try systemProxyHelper.register()
+          Self.storeHelperRegistrationStamp()
+        } catch {
+          // 刷新失败不记指纹，下次启动重试；状态退回后由下方分支接手。
+          RuntimeLog.emit(.systemProxyHelperRegisterFailed(detail: describe(error)))
+        }
+      }
+      if systemProxyHelper.status == .approved {
+        systemProxyApprovalRequired = false
+        return true
+      }
     case .notRegistered:
       do {
         try systemProxyHelper.register()
+        Self.storeHelperRegistrationStamp()
       } catch {
         RuntimeLog.emit(.systemProxyHelperRegisterFailed(detail: describe(error)))
       }
@@ -166,6 +181,19 @@ extension ProxyRuntimeController {
     return false
   }
 
+  private static func helperRegistrationDrifted(defaults: UserDefaults = .standard) -> Bool {
+    SystemProxyHelperRegistrationStamp.drifted(
+      plistData: SystemProxyHelperIdentity.launchDaemonPlistData,
+      storedStamp: defaults.string(forKey: SystemProxyHelperRegistrationStamp.defaultsKey))
+  }
+
+  private static func storeHelperRegistrationStamp(defaults: UserDefaults = .standard) {
+    guard let plistData = SystemProxyHelperIdentity.launchDaemonPlistData else { return }
+    defaults.set(
+      SystemProxyHelperRegistrationStamp.stamp(plistData),
+      forKey: SystemProxyHelperRegistrationStamp.defaultsKey)
+  }
+
   /// 登录项批准路径（issue #71）：打开系统设置的登录项面板并立即重试收敛；
   /// 批准完成前意图保持待应用、系统设置不变。
   func openSystemProxyHelperApproval() async {
diff --git a/ShadowsocksX-NG2/App/SystemProxyHelperService.swift b/ShadowsocksX-NG2/App/SystemProxyHelperService.swift
index 40259141..0ffb0977 100644
--- a/ShadowsocksX-NG2/App/SystemProxyHelperService.swift
+++ b/ShadowsocksX-NG2/App/SystemProxyHelperService.swift
@@ -1,3 +1,4 @@
+import CryptoKit
 import Foundation
 import ServiceManagement
 
@@ -12,12 +13,13 @@ protocol SystemProxyControlling {
 }
 
 /// helper 注册/审批状态缝（issue #71）：注册走 SMAppService.daemon；审批缺失
-/// 时 GUI 据此呈现登录项批准路径，不提供直接授权回退。单测以 fake 替换
-/// （真实注册会改动系统登录项状态）。
+/// 时 GUI 据此呈现登录项批准路径，不提供直接授权回退。unregister 供注册清单
+/// 漂移后的定义刷新使用。单测以 fake 替换（真实注册会改动系统登录项状态）。
 @MainActor
 protocol SystemProxyHelperServicing {
   var status: SystemProxyHelperStatus { get }
   func register() throws
+  func unregister() throws
   func openApprovalPath()
 }
 
@@ -49,11 +51,33 @@ struct SMAppServiceSystemProxyHelper: SystemProxyHelperServicing {
     try service.register()
   }
 
+  func unregister() throws {
+    try service.unregister()
+  }
+
   func openApprovalPath() {
     SMAppService.openSystemSettingsLoginItems()
   }
 }
 
+/// 注册清单漂移指纹（issue #71 后续）：launchd 对 SMAppService 提交的 job
+/// 沿用注册时的定义快照，app 更新改动 LaunchDaemon 清单不会自动生效（旧定义
+/// spawn 失败时 launchd 以 EX_CONFIG 节流循环）。以清单内容 SHA-256 检测漂移，
+/// 漂移才注销重注；审批与 bundle 签名绑定，重注不重新弹授权。
+enum SystemProxyHelperRegistrationStamp {
+  static let defaultsKey = "systemProxyHelperRegistrationStamp"
+
+  /// 清单不可读时不判漂移（无基准；未注册场景由注册路径自身兜底）。
+  static func drifted(plistData: Data?, storedStamp: String?) -> Bool {
+    guard let plistData else { return false }
+    return stamp(plistData) != storedStamp
+  }
+
+  static func stamp(_ data: Data) -> String {
+    SHA256.hash(data: data).map { String(format: "%02x", $0) }.joined()
+  }
+}
+
 /// 经特权 helper 的系统代理写入器（issue #71）：每个请求一条按需连接，
 /// MachService 连接触发 launchd 激活已注册的 LaunchDaemon。应答在
 /// helper 不可达、连接失效、报错或超时时以 typed 错误呈现。
diff --git a/ShadowsocksX-NG2/Domain/SystemProxyHelperContract.swift b/ShadowsocksX-NG2/Domain/SystemProxyHelperContract.swift
index e3bebbb6..7ecfae3b 100644
--- a/ShadowsocksX-NG2/Domain/SystemProxyHelperContract.swift
+++ b/ShadowsocksX-NG2/Domain/SystemProxyHelperContract.swift
@@ -17,6 +17,16 @@ enum SystemProxyHelperIdentity {
   static let plistName = "com.qiuyuzhou.ShadowsocksX-NG2.systemproxy.plist"
   static let launchdLabel = "com.qiuyuzhou.ShadowsocksX-NG2.systemproxy"
   static let clientCodeSigningIdentifier = "com.qiuyuzhou.ShadowsocksX-NG2"
+
+  /// App bundle 内 LaunchDaemon 清单内容（注册漂移指纹的基准）。helper 进程
+  /// 内没有 bundle，返回 nil，调用方按「无基准不动作」处理。Contents/Library
+  /// 不是资源目录，Bundle 资源 API 搜不到，按固定路径直读。
+  static var launchDaemonPlistData: Data? {
+    let url = Bundle.main.bundleURL
+      .appendingPathComponent("Contents/Library/LaunchDaemons")
+      .appendingPathComponent(plistName)
+    return try? Data(contentsOf: url)
+  }
 }
 
 /// helper XPC 应答：成功携带 typed 结果，失败携带 typed 错误族。
diff --git a/ShadowsocksX-NG2/LaunchDaemons/com.qiuyuzhou.ShadowsocksX-NG2.systemproxy.plist b/ShadowsocksX-NG2/LaunchDaemons/com.qiuyuzhou.ShadowsocksX-NG2.systemproxy.plist
index 32c50b9d..f0d5c9b9 100644
--- a/ShadowsocksX-NG2/LaunchDaemons/com.qiuyuzhou.ShadowsocksX-NG2.systemproxy.plist
+++ b/ShadowsocksX-NG2/LaunchDaemons/com.qiuyuzhou.ShadowsocksX-NG2.systemproxy.plist
@@ -2,12 +2,13 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
+	<!-- 可执行路径用 BundleProgram（SMAppService 专用键，bundle 相对）：
+	     ProgramArguments[0] 的相对路径按 _PATH_STDPATH（PATH）解析而非
+	     bundle，launchd 找不到程序会以 EX_CONFIG 循环 spawn 失败。 -->
+	<key>BundleProgram</key>
+	<string>Contents/MacOS/ShadowsocksX-NG2SystemProxyHelper</string>
 	<key>Label</key>
 	<string>com.qiuyuzhou.ShadowsocksX-NG2.systemproxy</string>
-	<key>ProgramArguments</key>
-	<array>
-		<string>Contents/MacOS/ShadowsocksX-NG2SystemProxyHelper</string>
-	</array>
 	<key>MachServices</key>
 	<dict>
 		<key>com.qiuyuzhou.ShadowsocksX-NG2.systemproxy</key>
diff --git a/ShadowsocksX-NG2/Tests/ProxyRuntimeControllerTests+AgentAndSystemProxy.swift b/ShadowsocksX-NG2/Tests/ProxyRuntimeControllerTests+AgentAndSystemProxy.swift
index d3327412..4603aa69 100644
--- a/ShadowsocksX-NG2/Tests/ProxyRuntimeControllerTests+AgentAndSystemProxy.swift
+++ b/ShadowsocksX-NG2/Tests/ProxyRuntimeControllerTests+AgentAndSystemProxy.swift
@@ -491,6 +491,43 @@ extension ProxyRuntimeControllerTests {
       recorder.recorded.contains(.systemProxyUnchanged),
       "跳过路径发事件行，实际 \(recorder.recorded)")
   }
+
+  /// LaunchDaemon 清单漂移（issue #71 后续）：launchd 沿用注册提交时的 job
+  /// 定义快照，app 更新改了清单后须注销重注才生效。已批准注册仅在清单指纹
+  /// 与注册时不一致时重注（审批与签名绑定，不重弹授权）；首次注册成功即记录
+  /// 指纹，指纹一致不动作。
+  func testHelperRegistrationRefreshesOnlyOnPlistDrift() async throws {
+    let defaults = UserDefaults.standard
+    let stampKey = SystemProxyHelperRegistrationStamp.defaultsKey
+    defer { defaults.removeObject(forKey: stampKey) }
+    defaults.removeObject(forKey: stampKey)
+
+    let seeded = try makeSeededCatalog()
+    systemProxyHelper.setStatus(.notRegistered)
+    let controller = makeController(probe: ProxyRuntimeFixture.FakeProbe.reachable())
+    try await controller.activate(seeded.server)
+    await controller.setAgentEnabled(true)
+    await controller.setSystemProxyEnabled(true)
+
+    let stampAfterRegister = try XCTUnwrap(
+      defaults.string(forKey: stampKey), "注册成功应记录 LaunchDaemon 清单指纹")
+    let registerCountAfterEnable = systemProxyHelper.registerCount
+    let unregisterCountAfterEnable = systemProxyHelper.unregisterCount
+
+    // 指纹一致：后续收敛不注销重注。
+    await controller.convergeSystemProxy()
+    XCTAssertEqual(systemProxyHelper.registerCount, registerCountAfterEnable, "指纹一致不重注")
+    XCTAssertEqual(systemProxyHelper.unregisterCount, unregisterCountAfterEnable)
+    XCTAssertEqual(controller.systemProxyState, .applied)
+
+    // 指纹漂移（模拟 app 更新改了清单）：注销重注一次并更新指纹。
+    defaults.set("drifted-stamp", forKey: stampKey)
+    await controller.convergeSystemProxy()
+    XCTAssertEqual(systemProxyHelper.unregisterCount, unregisterCountAfterEnable + 1, "漂移触发重注")
+    XCTAssertEqual(systemProxyHelper.registerCount, registerCountAfterEnable + 1)
+    XCTAssertEqual(defaults.string(forKey: stampKey), stampAfterRegister, "重注后记录当前清单指纹")
+    XCTAssertEqual(controller.systemProxyState, .applied, "重注后照常收敛应用")
+  }
 }
 
 /// 测试专用事件接收缝（issue #70 事件行断言用）。
diff --git a/ShadowsocksX-NG2/Tests/SystemProxyFakes.swift b/ShadowsocksX-NG2/Tests/SystemProxyFakes.swift
index d3bfe01f..f5d9f80b 100644
--- a/ShadowsocksX-NG2/Tests/SystemProxyFakes.swift
+++ b/ShadowsocksX-NG2/Tests/SystemProxyFakes.swift
@@ -37,7 +37,9 @@ extension ProxyRuntimeFixture {
   final class FakeSystemProxyHelperService: SystemProxyHelperServicing {
     private(set) var currentStatus: SystemProxyHelperStatus
     private(set) var registerCount = 0
+    private(set) var unregisterCount = 0
     private(set) var registerError: Error?
+    private(set) var unregisterError: Error?
     private(set) var openApprovalPathCount = 0
     /// register() 成功后迁移到的状态（模拟 BTM 批准立即达成）。
     var statusAfterRegister: SystemProxyHelperStatus = .approved
@@ -56,12 +58,22 @@ extension ProxyRuntimeFixture {
       registerError = error
     }
 
+    func setUnregisterError(_ error: Error?) {
+      unregisterError = error
+    }
+
     func register() throws {
       registerCount += 1
       if let registerError { throw registerError }
       currentStatus = statusAfterRegister
     }
 
+    func unregister() throws {
+      unregisterCount += 1
+      if let unregisterError { throw unregisterError }
+      currentStatus = .notRegistered
+    }
+
     func openApprovalPath() {
       openApprovalPathCount += 1
     }
diff --git a/ShadowsocksX-NG2/Tests/SystemProxyTests.swift b/ShadowsocksX-NG2/Tests/SystemProxyTests.swift
index d75017e2..810118bf 100644
--- a/ShadowsocksX-NG2/Tests/SystemProxyTests.swift
+++ b/ShadowsocksX-NG2/Tests/SystemProxyTests.swift
@@ -214,4 +214,29 @@ final class SystemProxyTests: XCTestCase {
       plan.writes.contains { $0.identifier == services[2].identifier },
       "没有 Proxies 实体的服务无需写入")
   }
+
+  // MARK: - 注册清单漂移指纹（issue #71 后续）
+
+  /// launchd 沿用注册提交时的 job 定义快照，清单变更须注销重注才生效；
+  /// 指纹检测决定是否重注。
+  func testRegistrationStampDriftDetection() {
+    let data = Data("plist-content".utf8)
+    XCTAssertTrue(
+      SystemProxyHelperRegistrationStamp.drifted(plistData: data, storedStamp: nil),
+      "无指纹（首次带检测代码启动）视为漂移")
+    XCTAssertTrue(
+      SystemProxyHelperRegistrationStamp.drifted(plistData: data, storedStamp: "outdated"),
+      "清单内容变更视为漂移")
+    XCTAssertFalse(
+      SystemProxyHelperRegistrationStamp.drifted(
+        plistData: data, storedStamp: SystemProxyHelperRegistrationStamp.stamp(data)),
+      "指纹一致不漂移")
+    XCTAssertFalse(
+      SystemProxyHelperRegistrationStamp.drifted(plistData: nil, storedStamp: nil),
+      "清单不可读无基准，不判漂移")
+    XCTAssertNotEqual(
+      SystemProxyHelperRegistrationStamp.stamp(Data("a".utf8)),
+      SystemProxyHelperRegistrationStamp.stamp(Data("b".utf8)),
+      "不同清单内容指纹不同")
+  }
 }
diff --git a/ShadowsocksX-NG2/project.yml b/ShadowsocksX-NG2/project.yml
index 3904d0d9..b5fc7688 100644
--- a/ShadowsocksX-NG2/project.yml
+++ b/ShadowsocksX-NG2/project.yml
@@ -33,8 +33,9 @@ targets:
             subpath: Contents/Library/LaunchAgents
       # 特权系统代理 helper 的 LaunchDaemon 注册清单（issue #71）：
       # SMAppService.daemon(plistName:) 从 bundle 内
-      # Contents/Library/LaunchDaemons/ 读取；ProgramArguments 用 bundle 相对
-      # 路径；MachServices 键支撑 on-demand 激活。
+      # Contents/Library/LaunchDaemons/ 读取；可执行路径用 BundleProgram 键
+      # （bundle 相对；ProgramArguments 的相对路径按 PATH 解析会 spawn 失败）；
+      # MachServices 键支撑 on-demand 激活。
       - path: LaunchDaemons/com.qiuyuzhou.ShadowsocksX-NG2.systemproxy.plist
         buildPhase:
           copyFiles: