Abstract: Ainu is the only ethnic minority recognized by the Japanese government. Over the past one hundred years, a powerful policy of assimilation for national languages has been implemented in the process of nationalization dominated by the state, which has a profound impact on Ainus national identity. Language assimilation is often accompanied by the transfer of national identity, but the relationship between them is not inevitable. Language assimilation and national identity differ in both speed and degree. Language assimilation can be basically completed in a short time，but national identity needs a long time to accept. For now，Japan has completed the assimilation of Ainu national language, but the transfer of the national identity of the Ainu people has not been fully realized. Based on objective historical data and realistic investigation, this paper describes the basic historical outline of Ainu, focusing on the formulation, implementation and adjustment of the Ainu language assimilation policy, the acceptance, change and resistance of the Ainu people to relevant policies. It then analyzes the main causes of language assimilation policy and its impact on the language life of the Ainu people. Finally, it discusses in depth the results of language assimilation and its relationship with national identity, hoping to provide valuable reference for the research of Ainu national issues.

Key words: Ainu, language policy, language assimilation, national identity