diff --git a/netx_api/config_sync_router.py b/netx_api/config_sync_router.py
index a33dd58..f397a80 100644
--- a/netx_api/config_sync_router.py
+++ b/netx_api/config_sync_router.py
@@ -24,6 +24,7 @@ from .config_sync_service import (
     list_snapshots,
     pause_cycle,
     resume_cycle,
+    stop_cycle,
     update_policy,
 )
 from .db import get_db
@@ -137,6 +138,23 @@ def api_resume_cycle(
     return out.model_dump()
 
 
+@router.post("/cycles/{cycle_id}/stop")
+def api_stop_cycle(cycle_id: str, request: Request, db: Session = Depends(get_db)):
+    out = stop_cycle(db, cycle_id)
+    uid, uname = _actor(request)
+    write_audit(
+        db,
+        action="config_sync.stop",
+        actor_user_id=uid,
+        actor_username=uname,
+        method="POST",
+        path=f"/v1/config-sync/cycles/{cycle_id}/stop",
+        status_code=200,
+        detail={"cycle_id": cycle_id},
+    )
+    return out.model_dump()
+
+
 @router.get("/snapshots")
 def api_list_snapshots(
     page: int = Query(default=1, ge=1),
diff --git a/netx_api/config_sync_service.py b/netx_api/config_sync_service.py
index 1f5cd9f..80a40e7 100644
--- a/netx_api/config_sync_service.py
+++ b/netx_api/config_sync_service.py
@@ -377,7 +377,7 @@ def pause_cycle(db: Session, cycle_id: str) -> ConfigSyncCycleOut:
     row = db.get(ConfigSyncCycle, cycle_id)
     if not row:
         raise HTTPException(status_code=404, detail="cycle_not_found")
-    if str(row.status) != "running":
+    if str(row.status) not in ("running", "pending"):
         raise HTTPException(status_code=400, detail="cycle_not_running")
     row.status = "paused"
     db.commit()
@@ -407,6 +407,45 @@ def resume_cycle(db: Session, cycle_id: str) -> ConfigSyncCycleOut:
     return cycle_to_out(row)
 
 
+def stop_cycle(db: Session, cycle_id: str) -> ConfigSyncCycleOut:
+    """Cancel remaining work and close the cycle (running/paused/pending)."""
+    row = db.get(ConfigSyncCycle, cycle_id)
+    if not row:
+        raise HTTPException(status_code=404, detail="cycle_not_found")
+    if str(row.status) not in ("running", "paused", "pending"):
+        raise HTTPException(status_code=400, detail="cycle_not_active")
+    now = _utcnow()
+    pending = (
+        db.query(ConfigSyncTask)
+        .filter(
+            ConfigSyncTask.cycle_id == cycle_id,
+            ConfigSyncTask.status.in_(("pending", "running")),
+        )
+        .all()
+    )
+    for task in pending:
+        # In-flight workers may still finish and overwrite; pending must not start.
+        if str(task.status) == "pending":
+            task.status = "cancelled"
+            task.message = "stopped_by_user"
+            task.ended_at = now
+        else:
+            task.message = (str(task.message or "") + " · stop_requested")[:1020]
+    row.status = "cancelled"
+    row.error_message = "stopped_by_user"
+    row.ended_at = now
+    db.commit()
+    sync_cycle_progress(db, cycle_id)
+    db.refresh(row)
+    try:
+        from .config_sync_runner import _release_pool
+
+        _release_pool(cycle_id)
+    except Exception:
+        pass
+    return cycle_to_out(row)
+
+
 def dashboard(db: Session) -> ConfigSyncDashboardOut:
     policy = ensure_policy(db)
     snap_count = int(db.query(func.count()).select_from(NeConfigSnapshot).scalar() or 0)
@@ -629,7 +668,7 @@ def finalize_cycle(db: Session, cycle_id: str) -> None:
     cycle = db.get(ConfigSyncCycle, cycle_id)
     if not cycle:
         return
-    if str(cycle.status) == "paused":
+    if str(cycle.status) in ("paused", "cancelled"):
         return
     pending = (
         db.query(func.count())
@@ -642,6 +681,8 @@ def finalize_cycle(db: Session, cycle_id: str) -> None:
         return
     sync_cycle_progress(db, cycle_id)
     db.refresh(cycle)
+    if str(cycle.status) in ("paused", "cancelled"):
+        return
     # Cycle outcome is about finishing the run, not per-NE results.
     # Individual task failures stay in fail_count for retry/dashboard.
     cycle.status = "success"
diff --git a/web/src/i18n/en.ts b/web/src/i18n/en.ts
index ccaff76..a86dcbf 100644
--- a/web/src/i18n/en.ts
+++ b/web/src/i18n/en.ts
@@ -139,9 +139,12 @@ const en = {
     retryFailed: "Retry failed",
     pause: "Pause",
     resume: "Resume",
+    stop: "Stop",
+    confirmStop: "Stop this cycle and cancel remaining NE tasks?",
     started: "Sync cycle started",
     paused: "Paused",
     resumed: "Resumed",
+    stopped: "Sync cycle stopped",
     policyTitle: "Sync policy",
     policySaved: "Policy saved",
     enabled: "Enable scheduled sync",
@@ -178,6 +181,7 @@ const en = {
       started: "Started",
       ended: "Ended",
       message: "Message",
+      actions: "Actions",
     },
   },
   networkDevices: {
diff --git a/web/src/i18n/zh.ts b/web/src/i18n/zh.ts
index f989db0..03ed73c 100644
--- a/web/src/i18n/zh.ts
+++ b/web/src/i18n/zh.ts
@@ -139,9 +139,12 @@ const zh = {
     retryFailed: "一键重试失败",
     pause: "暂停",
     resume: "继续",
+    stop: "停止",
+    confirmStop: "停止后将取消未执行的网元任务，确定停止本轮同步？",
     started: "已启动同步周期",
     paused: "已暂停",
     resumed: "已继续",
+    stopped: "已停止同步周期",
     policyTitle: "同步策略",
     policySaved: "策略已保存",
     enabled: "启用周期调度",
@@ -178,6 +181,7 @@ const zh = {
       started: "开始",
       ended: "结束",
       message: "消息",
+      actions: "操作",
     },
   },
   networkDevices: {
diff --git a/web/src/pages/ConfigSyncPage.tsx b/web/src/pages/ConfigSyncPage.tsx
index 509a386..abbdeb2 100644
--- a/web/src/pages/ConfigSyncPage.tsx
+++ b/web/src/pages/ConfigSyncPage.tsx
@@ -8,6 +8,7 @@ import {
   fetchConfigSyncDashboard,
   pauseConfigSyncCycle,
   resumeConfigSyncCycle,
+  stopConfigSyncCycle,
   updateConfigSyncPolicy,
 } from "../services/api";
 import { queryKeys } from "../constants/queryKeys";
@@ -48,7 +49,9 @@ export function ConfigSyncPage() {
     staleTime: 1000,
     refetchInterval: (q) => {
       const running = q.state.data?.running_cycle;
-      return running && (running.status === "running" || running.status === "paused") ? POLL_MS : false;
+      return running && (running.status === "running" || running.status === "paused" || running.status === "pending")
+        ? POLL_MS
+        : false;
     },
   });
 
@@ -151,6 +154,15 @@ export function ConfigSyncPage() {
     onError: (err) => showError(String(err)),
   });
 
+  const stopMut = useMutation({
+    mutationFn: (id: string) => stopConfigSyncCycle(id),
+    onSuccess: async () => {
+      showOk(t("configSync.stopped"));
+      await refresh();
+    },
+    onError: (err) => showError(String(err)),
+  });
+
   const dash = dashQuery.data;
   const running = dash?.running_cycle;
   const last = dash?.last_cycle;
@@ -193,7 +205,7 @@ export function ConfigSyncPage() {
           >
             {t("configSync.retryFailed")}
           </button>
-          {running?.status === "running" ? (
+          {running?.status === "running" || running?.status === "pending" ? (
             <button type="button" onClick={() => pauseMut.mutate(running.id)} disabled={pauseMut.isPending}>
               {t("configSync.pause")}
             </button>
@@ -203,6 +215,17 @@ export function ConfigSyncPage() {
               {t("configSync.resume")}
             </button>
           ) : null}
+          {running && (running.status === "running" || running.status === "paused" || running.status === "pending") ? (
+            <button
+              type="button"
+              onClick={() => {
+                if (window.confirm(t("configSync.confirmStop"))) stopMut.mutate(running.id);
+              }}
+              disabled={stopMut.isPending}
+            >
+              {t("configSync.stop")}
+            </button>
+          ) : null}
         </div>
       </div>
 
@@ -369,6 +392,7 @@ export function ConfigSyncPage() {
             <th>{t("configSync.col.progress")}</th>
             <th>{t("configSync.col.started")}</th>
             <th>{t("configSync.col.ended")}</th>
+            <th>{t("configSync.col.actions")}</th>
           </tr>
         </thead>
         <tbody>
@@ -393,11 +417,36 @@ export function ConfigSyncPage() {
               </td>
               <td>{c.started_at ? formatSystemTime(c.started_at) : "-"}</td>
               <td>{c.ended_at ? formatSystemTime(c.ended_at) : "-"}</td>
+              <td>
+                <div className="btn-row">
+                  {c.status === "running" || c.status === "pending" ? (
+                    <button type="button" onClick={() => pauseMut.mutate(c.id)} disabled={pauseMut.isPending}>
+                      {t("configSync.pause")}
+                    </button>
+                  ) : null}
+                  {c.status === "paused" ? (
+                    <button type="button" onClick={() => resumeMut.mutate(c.id)} disabled={resumeMut.isPending}>
+                      {t("configSync.resume")}
+                    </button>
+                  ) : null}
+                  {c.status === "running" || c.status === "paused" || c.status === "pending" ? (
+                    <button
+                      type="button"
+                      onClick={() => {
+                        if (window.confirm(t("configSync.confirmStop"))) stopMut.mutate(c.id);
+                      }}
+                      disabled={stopMut.isPending}
+                    >
+                      {t("configSync.stop")}
+                    </button>
+                  ) : null}
+                </div>
+              </td>
             </tr>
           ))}
           {!cycles.length ? (
             <tr>
-              <td colSpan={7} className="muted">
+              <td colSpan={8} className="muted">
                 {t("configSync.cyclesEmpty")}
               </td>
             </tr>
diff --git a/web/src/services/api.ts b/web/src/services/api.ts
index 803539a..ba2bc5e 100644
--- a/web/src/services/api.ts
+++ b/web/src/services/api.ts
@@ -708,6 +708,9 @@ export const pauseConfigSyncCycle = (cycleId: string) =>
 export const resumeConfigSyncCycle = (cycleId: string) =>
   apiPost<ConfigSyncCycle>(`/v1/config-sync/cycles/${encodeURIComponent(cycleId)}/resume`, {});
 
+export const stopConfigSyncCycle = (cycleId: string) =>
+  apiPost<ConfigSyncCycle>(`/v1/config-sync/cycles/${encodeURIComponent(cycleId)}/stop`, {});
+
 export const fetchConfigSyncCycleTasks = (params: {
   cycleId: string;
   page?: number;