diff --git a/ledis/t_zset.go b/ledis/t_zset.go
index 5d6bfb3..964361e 100644
--- a/ledis/t_zset.go
+++ b/ledis/t_zset.go
@@ -899,7 +899,7 @@ func (db *DB) ZUnionStore(destKey []byte, srcKeys [][]byte, weights []int64, agg
 		}
 		for _, pair := range scorePairs {
 			if score, ok := destMap[String(pair.Member)]; !ok {
-				destMap[String(pair.Member)] = pair.Score
+				destMap[String(pair.Member)] = pair.Score * weights[i]
 			} else {
 				destMap[String(pair.Member)] = aggregateFunc(score, pair.Score*weights[i])
 			}
@@ -966,7 +966,7 @@ func (db *DB) ZInterStore(destKey []byte, srcKeys [][]byte, weights []int64, agg
 		}
 		for _, pair := range scorePairs {
 			if score, ok := destMap[String(pair.Member)]; !ok {
-				destMap[String(pair.Member)] = pair.Score
+				destMap[String(pair.Member)] = pair.Score * weights[i]
 			} else {
 				keptMembers = append(keptMembers, pair.Member)
 				destMap[String(pair.Member)] = aggregateFunc(score, pair.Score*weights[i])
diff --git a/ledis/t_zset_test.go b/ledis/t_zset_test.go
index a772360..a2232d3 100644
--- a/ledis/t_zset_test.go
+++ b/ledis/t_zset_test.go
@@ -338,7 +338,7 @@ func TestZInterStore(t *testing.T) {
 	db.ZAdd(key2, ScorePair{2, []byte("three")})
 
 	keys := [][]byte{key1, key2}
-	weights := []int64{1, 2}
+	weights := []int64{2, 3}
 	out := []byte("out")
 
 	n, err := db.ZInterStore(out, keys, weights, AggregateSum)
@@ -352,7 +352,7 @@ func TestZInterStore(t *testing.T) {
 	if err != nil {
 		t.Fatal(err.Error())
 	}
-	if v != 5 {
+	if v != 8 {
 		t.Fatal("invalid value ", v)
 	}
 
@@ -370,7 +370,7 @@ func TestZInterStore(t *testing.T) {
 	if err != nil {
 		t.Fatal(err.Error())
 	}
-	if v != 1 {
+	if v != 2 {
 		t.Fatal("invalid value ", v)
 	}