Bayi or Bayizhen is a town and township in Tibet and capital of Nyingchi County. It lies on the Nyang River at an altitude of 2994 metres (9826 feet). Bayi is an important timber and wool producing town, known historically before the 1960s as Lhabagar. By road it is 405 km east of Lhasa on the way to Chengdu.
The new town completely absorbed the ancient village of Drakchi, which used to stand on this site. The population is now mostly Han Chinese. The Bayi Zanchen bridge crosses the Nyang-chu or Nyang River here.