Since the beginning of the 21stcentury,white extremist groups have become increasingly active online.They use the internet to promote white supremacy,raise funds,recruit members,and get mobilized against Muslims,immigrants,Jews,blacks and other minority groups in extreme ways.Online white extremism has the characteristics of young audience,diverse in information,strong incitement and privacy.Although the United States has strengthened the governance of online white extremism in terms of macro strategy,governance system,legal system and community governance,it is difficult to effectively curb white extremism due to freedom of speech,networked operation of economy,unbalanced access level on the internet,and uneven digital literacy and skills.