diff --git a/scripts/nas_sync/sync_parquet.sh b/scripts/nas_sync/sync_parquet.sh
index 9fc4c17..0c875c2 100644
--- a/scripts/nas_sync/sync_parquet.sh
+++ b/scripts/nas_sync/sync_parquet.sh
@@ -8,6 +8,19 @@ VPS=Administrator@49.232.102.198
 DATA=/volume1/stock/sanguo_vnpy_v2/data
 LOG=/volume1/stock/sanguo_vnpy_v2/data_backup/parquet.log
 
+# 互斥锁(2026-08-21): 触发源两路=周日钩子(sync_valuation_daily.sh)与 DSM id=6 周日04:00,
+# 双 scp -r 并发写同文件会撕损; mkdir 原子锁, >6h 视陈旧覆盖(单跑 70min 远不到)。
+LOCK=/volume1/stock/sanguo_vnpy_v2/data_backup/parquet_full.lock
+if [ -d "$LOCK" ]; then
+  if [ -z "$(find "$LOCK" -maxdepth 0 -mmin +360 2>/dev/null)" ]; then
+    echo "[$(date '+%T')] lock held, another full sync running -> skip" >> "$LOG"
+    exit 0
+  fi
+  rmdir "$LOCK" 2>/dev/null
+fi
+mkdir "$LOCK" 2>/dev/null || { echo "[$(date '+%T')] lock mkdir fail" >> "$LOG"; exit 1; }
+trap 'rmdir "$LOCK" 2>/dev/null' EXIT
+
 echo "=== parquet scp start $(date) ===" >> "$LOG"
 cd "$DATA" || { echo "cd fail" >> "$LOG"; exit 1; }