The national identity of frontier ethnic is gradually formed in the process of historical development relying on inner consciousness and external force,the rulers of Tang Dynasty strengthened their identity,political,and cultural identity through the patriarchal clan system,cultivated virtue,canonization,tribute and cultural communication. Taking history as a mirror,the construction of national identity should take the dissemination and approval of mainstream culture as the core content,and take identity as an important means,and take the legitimacy of regime as a breakthrough.