Yi People's customary law plays an important role in mediating dispute in the settlement of nonlitigation disputes.This paper discusses the positive role of Yi People's customary law in resolving contradictions and promoting social harmony.It also analyzes the negative role of Yi People's customary law such as it crams into the space of modern legal system and makes disputes of vulgarity hard to resolve.Then it puts forth some suggestions on settlement of nonlitigation disputes including strengthening"Degu"training and setting up a"Dispute Resolution Center"and so on.