外太空的莫扎特

黄渤

— Dawang

荣梓杉

— Xiaotian

陈思诚

— Mozart (voice)

黄杨钿甜

— Ding Jieling

姚晨

— Niu Yuxia

范偉

— Grandpa Xiaotian

贾冰

— Teacher Deng

许君聪

— Scarface

梅婷

— Ren Xiaotian's mother

Lang Lang

— Lang Lang

黄觉

— Ding Jieling's father

于洋

Fan Tiantian

— Xue Xihao's mother

桑平

— Ma Yuan's father

Yang Jinci

— Twins' father

Li Mingxuan

— Police

李澤宇

黃星羱

— Ouyang Baoluo

于波

— [Mo Mo's father]