The migrant workers' self-organizations mainly include formal self-organizations registered in government departments and informal self-organizations totally in spontaneous and autogenic states . The formal self-organizations tend to have large scale，obvious procedure and clear goal；the development of activity is regular；the social influence is visible. The informal self-organizations tend to have small scale，potential existence and strong arbitrariness；the activity time and procedure are irregular while the degree of intimacy is higher；the level of trust，sense of gain and sense of belonging are also higher. For the new-generation migrant workers，the self-organizations including the clansmen association，interest groups，etc. could help them kill the time and resolve their vanity and boringness. Meanwhile they could engage in information exchange and technical exchange through social interaction，and solve the daily affairs in work and life. The migrant workers are often in the state of floating state，hence they often lack social support. Under this situation，the self-organizations could provide the mechanism for safety valve to the migrant workers and solve their negative emotions caused by work and life experiences.