diff --git a/ledis/t_zset.go b/ledis/t_zset.go
index 7cf753a..fe11df8 100644
--- a/ledis/t_zset.go
+++ b/ledis/t_zset.go
@@ -583,9 +583,10 @@ func (db *DB) zRange(key []byte, min int64, max int64, offset int, count int, re
 		return []ScorePair{}, nil
 	}
 
-	nv := 64
-	if count > 0 {
-		nv = count
+	nv := count
+	// count may be very large, so we must limit it for below mem make.
+	if nv <= 0 || nv > 1024 {
+		nv = 64
 	}
 
 	v := make([]ScorePair, 0, nv)