hello is there a night bus from pingyao to xian?

Hi, no direct bus leaves for the route. Alternatively, I suggest you take a bus to Taiyuan first. It takes around 2 hours and buses are scheduled from 06:15 to 20:00. You will get to Jiannan Bus Station. Then take a taxi to local General Bus Station to catch a direct bus to Xian in around 8 hours and buses are available from 08:00 to 16:00.