diff --git a/tushare/src/storage.py b/tushare/src/storage.py
index c3ca757..a348116 100644
--- a/tushare/src/storage.py
+++ b/tushare/src/storage.py
@@ -68,6 +68,11 @@ def save_candles(df: pd.DataFrame, db_url: str = DEFAULT_DB_URL):
         df = df.copy()
         df = df.where(pd.notna(df), None)
         records = df.to_dict(orient="records")
+        # pandas float 列的 None 会被转为 NaN，需手动清理后再存入数据库
+        for record in records:
+            for key, val in record.items():
+                if isinstance(val, float) and val != val:  # NaN != NaN
+                    record[key] = None
         with conn.cursor() as cur:
             cur.executemany(
                 """
diff --git a/web/backend/internal/store/futures.go b/web/backend/internal/store/futures.go
index da8b100..8fb4480 100644
--- a/web/backend/internal/store/futures.go
+++ b/web/backend/internal/store/futures.go
@@ -149,9 +149,11 @@ func (s *FuturesStore) ListCandles(tsCode, start, end string) ([]Candle, error)
 		return nil, ErrMissingTsCode
 	}
 	q := `SELECT ts_code, trade_date,
-	      COALESCE(open, 0), COALESCE(high, 0), COALESCE(low, 0), COALESCE(close, 0),
-	      COALESCE(vol, 0), COALESCE(amount, 0),
-	      COALESCE(oi, 0), COALESCE(oi_chg, 0), COALESCE(pre_close, 0)
+	      COALESCE(NULLIF(open, 'NaN'::real), 0), COALESCE(NULLIF(high, 'NaN'::real), 0),
+	      COALESCE(NULLIF(low, 'NaN'::real), 0), COALESCE(NULLIF(close, 'NaN'::real), 0),
+	      COALESCE(NULLIF(vol, 'NaN'::real), 0), COALESCE(NULLIF(amount, 'NaN'::real), 0),
+	      COALESCE(NULLIF(oi, 'NaN'::real), 0), COALESCE(NULLIF(oi_chg, 'NaN'::real), 0),
+	      COALESCE(NULLIF(pre_close, 'NaN'::real), 0)
 	      FROM candles WHERE ts_code = $1`
 	args := []any{tsCode}
 	n := 1