Abstract:The Yi nationality’s customary law plays an important role in the construction of the new rural of Liangshan Prefecture.The Yi nationality’s customory law combines morals with penetrates into Yi nationality’s society.Its publicity,cohesion and centripetal force have extensive constraint function.The family groups of Liangshan Yi nationality have national morals,focus on the harmony of groups and families and play a key role in the process of mediating disputes,conciliating conflict,keeping social stability,enhencing social harmony and constructing the new socialist rural.