diff --git a/src/t_zset.c b/src/t_zset.c
index 3e76ebd1..8b166209 100644
--- a/src/t_zset.c
+++ b/src/t_zset.c
@@ -1521,7 +1521,10 @@ void zunionInterGenericCommand(redisClient *c, robj *dstkey, int op) {
 
                 score = src[0].weight * zval.score;
                 for (j = 1; j < setnum; j++) {
-                    if (zuiFind(&src[j],&zval,&value)) {
+                    if (src[j].subject == src[0].subject) {
+                        value = zval.score*src[j].weight;
+                        zunionInterAggregate(&score,value,aggregate);
+                    } else if (zuiFind(&src[j],&zval,&value)) {
                         value *= src[j].weight;
                         zunionInterAggregate(&score,value,aggregate);
                     } else {