Tchangmargarya is a genus of large operculate freshwater snails, aquatic gastropod molluscs in the family Viviparidae.
Tchangmargarya originally was a subgenus of Margarya, and is elevated to a full genus based on molecular phylogeny and comparative morphology study.
This genus appear to be endemic to Yangzong Lake and lakes in Stone Forest in Yunnan Province in the China.
There are 3 extant species of Tchangmargarya: