Knowledge of the family Assamiidae in the Eastern Himalayas is primarily concentrated from Nepal, while Bhutan, Xizang, and northeastern India remain much less studied. Herein, a new genus, Linzhiassamiagen. nov., is described from Xizang, China, along with two new species, Linzhiassamia medogensissp. nov. and Linzhiassamia zayuensissp. nov. These represents the first records of the family Assamiidae from Xizang. A comparative analysis with other continental Asian Assamiidae is undertaken, with a focus on genital morphology. Potential closest relatives are identified, including the genus Dhaulagirius Martens, 1977 from Nepal.