diff --git a/app/cli.py b/app/cli.py
index 53361be..c7b3bcf 100644
--- a/app/cli.py
+++ b/app/cli.py
@@ -312,6 +312,26 @@ def report():
         raise typer.Exit(code=1)
 
 
+@app.command()
+def sync_sources():
+    """M3/M9 辅助：把 deduped 已合并的多来源同步到 events/Qdrant/MySQL"""
+    from dedup.pipeline import sync_sources_from_deduped
+
+    try:
+        stats = sync_sources_from_deduped()
+        typer.echo(
+            f"\n✅ 来源同步完成: 扫描 {stats['deduped_scanned']} 个唯一篇, "
+            f"多来源 {stats['multi_source']} 个, "
+            f"events 更新 {stats['events_updated']}, "
+            f"Qdrant 更新 {stats['qdrant_updated']}, "
+            f"MySQL 更新 {stats['db_updated']}"
+        )
+    except Exception as e:
+        logger.exception("来源同步失败")
+        typer.echo(f"❌ 来源同步出错: {e}", err=True)
+        raise typer.Exit(code=1)
+
+
 @app.command()
 def pipeline(
     skip_report: bool = typer.Option(
diff --git a/dedup/pipeline.py b/dedup/pipeline.py
index 4892b36..628ef5a 100644
--- a/dedup/pipeline.py
+++ b/dedup/pipeline.py
@@ -172,10 +172,160 @@ def _merge_duplicate_source(article: ProcessedArticle, result: DedupResult) -> N
         )
         logger.debug("来源合并: %s → %s (sources=%s)",
                      article.source_id, result.matched_url_hash, merged)
+        # 同步到已生成的 events / Qdrant，避免“deduped 有多来源但 DB 没有”
+        _sync_merged_sources_downstream(result.matched_url_hash, merged)
     except Exception as e:
         logger.exception("来源合并失败 %s: %s", target, e)
 
 
+def _sync_event_source_ids(url_hash: str, source_ids: list[str]) -> int:
+    """把合并后的 source_ids 同步到已生成的 events JSON。"""
+    updated = 0
+    for ev_path in sorted(Path("data/events").glob(f"*/{url_hash}.json")):
+        try:
+            data = json.loads(ev_path.read_text(encoding="utf-8"))
+            if data.get("source_ids") != source_ids:
+                data["source_ids"] = list(source_ids)
+                ev_path.write_text(
+                    json.dumps(data, indent=2, ensure_ascii=False),
+                    encoding="utf-8",
+                )
+                logger.info("来源合并同步 events: %s -> %s", ev_path, source_ids)
+                updated += 1
+        except Exception as e:
+            logger.exception("同步 events 来源失败 %s: %s", ev_path, e)
+    return updated
+
+
+def _sync_qdrant_source_ids(url_hash: str, source_ids: list[str]) -> int:
+    """把合并后的 source_ids 同步到 Qdrant 中已存在的向量点。"""
+    emb_paths = sorted(Path("data/embeddings").glob(f"*/{url_hash}.json"))
+    if not emb_paths:
+        return 0
+
+    event_path = next(Path("data/events").glob(f"*/{url_hash}.json"), None)
+    if event_path is None:
+        return 0
+
+    try:
+        article_data = json.loads(event_path.read_text(encoding="utf-8"))
+    except Exception as e:
+        logger.warning("读取 events 失败，跳过 Qdrant 来源同步 %s: %s", event_path, e)
+        return 0
+
+    try:
+        from vectorstore.client import VectorStore, make_qdrant_client
+        from vectorstore.pipeline import _build_payload
+
+        client = make_qdrant_client()
+        store = VectorStore(client)
+        try:
+            payload = _build_payload(article_data)
+            for emb_path in emb_paths:
+                emb_data = json.loads(emb_path.read_text(encoding="utf-8"))
+                store.upsert([{
+                    "id": url_hash,
+                    "vector": emb_data["vector"],
+                    "payload": payload,
+                }])
+        finally:
+            store.close()
+        logger.info("来源合并同步 Qdrant: %s -> %s", url_hash, source_ids)
+        return len(emb_paths)
+    except Exception as e:
+        logger.warning("同步 Qdrant 来源失败 %s: %s", url_hash, e)
+        return 0
+
+
+def _sync_merged_sources_downstream(url_hash: str, source_ids: list[str]) -> None:
+    """去重合并来源后，同步更新 events 与 Qdrant 中已存在的下游数据。"""
+    _sync_event_source_ids(url_hash, source_ids)
+    _sync_qdrant_source_ids(url_hash, source_ids)
+
+
+def sync_sources_from_deduped() -> dict:
+    """历史数据回填：扫描所有 deduped 唯一篇，把多来源同步到 events/Qdrant/MySQL。
+
+    该函数用于修复“deduped 已合并多来源，但旧 events/数据库未更新”的历史数据。
+    """
+    stats = {
+        "deduped_scanned": 0,
+        "multi_source": 0,
+        "events_updated": 0,
+        "qdrant_updated": 0,
+        "db_updated": 0,
+    }
+
+    targets = sorted(Path("data/deduped").glob("*/uniques/*.json"))
+    for target in targets:
+        try:
+            data = json.loads(target.read_text(encoding="utf-8"))
+        except Exception:
+            continue
+        stats["deduped_scanned"] += 1
+
+        raw_ids = data.get("source_ids") or [data.get("source_id")]
+        source_ids = list(dict.fromkeys(x for x in raw_ids if x))
+        if len(source_ids) <= 1:
+            continue
+
+        stats["multi_source"] += 1
+        url_hash = data.get("url_hash", target.stem)
+        stats["events_updated"] += _sync_event_source_ids(url_hash, source_ids)
+        stats["qdrant_updated"] += _sync_qdrant_source_ids(url_hash, source_ids)
+        stats["db_updated"] += _update_db_sources(url_hash, source_ids)
+
+    logger.info(
+        "来源回填完成: scanned=%d multi=%d events=%d qdrant=%d db=%d",
+        stats["deduped_scanned"], stats["multi_source"],
+        stats["events_updated"], stats["qdrant_updated"], stats["db_updated"],
+    )
+    return stats
+
+
+def _update_db_sources(url_hash: str, source_ids: list[str]) -> int:
+    """根据最新 events 来源，更新 MySQL news_event 中该文章的 source/sources。"""
+    event_path = next(Path("data/events").glob(f"*/{url_hash}.json"), None)
+    if event_path is None:
+        return 0
+    try:
+        article_data = json.loads(event_path.read_text(encoding="utf-8"))
+    except Exception:
+        return 0
+
+    try:
+        from scheduler.reporter import _article_source_label, _article_sources_full
+        source_label = _article_source_label(article_data)
+        source_list = _article_sources_full(article_data)
+        if not source_label and not source_list:
+            return 0
+
+        from report_db import connect
+        conn = connect()
+        try:
+            with conn.cursor() as cur:
+                cur.execute(
+                    """
+                    UPDATE news_event
+                    SET source = %s, sources = %s
+                    WHERE section = 'intl' AND url = %s
+                    """,
+                    (
+                        source_label,
+                        json.dumps(source_list, ensure_ascii=False) if source_list else None,
+                        article_data.get("url"),
+                    ),
+                )
+                updated = cur.rowcount
+            conn.commit()
+            return updated or 0
+        finally:
+            conn.close()
+    except Exception as e:
+        logger.warning("同步 MySQL 来源失败 %s: %s", url_hash, e)
+        return 0
+
+
 def _layer_num(result: DedupResult) -> int:
     """DedupResult → 命中层编号。"""
     if result.matched_layer is None:
diff --git a/docs/pipeline.md b/docs/pipeline.md
index b79fd8f..a0ed7f9 100644
--- a/docs/pipeline.md
+++ b/docs/pipeline.md
@@ -45,6 +45,10 @@ uv run en-news extract --source cnbc
   2. 正文 hash 一致 → 重复
   3. SimHash 汉明距离 ≤ 阈值 → 模糊重复
 - 跨源合并：重复篇的来源 ID 会追加到保留唯一篇的 `source_ids`，日报可展示多来源。
+- 合并后会同步更新已生成的 `events` 与 Qdrant payload；历史数据可执行：
+  ```bash
+  uv run en-news sync-sources
+  ```
 
 ```bash
 uv run en-news dedup
diff --git a/docs/usage.md b/docs/usage.md
index 12b6b68..0ada3d8 100644
--- a/docs/usage.md
+++ b/docs/usage.md
@@ -12,6 +12,7 @@
 | `index` | M6 写入 Qdrant | `--recreate` 重建；`--date/-d` 指定日期；`--all` 全量回灌 |
 | `search` | M6 语义检索 | 必需 query；`--top-k` 返回条数 |
 | `report` | M9 生成日报并入库 | 无 |
+| `sync-sources` | 把 deduped 已合并的多来源同步到 events/Qdrant/MySQL | 无 |
 | `pipeline` | M2→M6（+日报） | `--skip-report` 跳过日报；`--date/-d` 指定日期 |
 | `mcp-server` | M8 启动 MCP 服务 | 无 |
 
@@ -38,6 +39,9 @@ uv run en-news index --date 20260801
 # 全量回灌历史向量（--recreate 搭配 --all 时只会在首个日期重建 collection）
 uv run en-news index --all
 uv run en-news embed --all
+
+# 修复历史多来源：把 deduped 中已合并的 source_ids 同步到 events/Qdrant/MySQL
+uv run en-news sync-sources
 ```
 
 ## 2. Shell 脚本