Bisu (Chinese: 毕苏语) is a Loloish language of Thailand, with a couple thousand speakers in China.
Varieties are Bisu proper (Mbisu) and Laomian (Guba), considered by Pelkey to be distinct languages.
Within Yunnan, it is spoken mostly in Pu'er Prefecture, as well as neighboring parts of Xishuangbanna.
In Thailand, two dialects of Bisu are spoken in the following villages of Phan District, Chiang Rai Province (Bisuyu Yanjiu 2002:152).
In Laos, Bisu (pi33 su44; also called Lao-Phai) is spoken in Phudokcham village, Phongxaly District.