Drawing on both qualitative and quantitative data,this paper explores the patterns, status,and determinants of identificational assimilation of young migrants in Beijing. Findings suggest that,migrants in Beijing have a stronger desire to be integrated,though there is a deep gap between desire and outcome of identificational assimilation. Contrary to findings of the other studies,all else equal,the young migrants are less assimilated into the host society than the older ones, while rural-urban migrants have a stronger desire to be assimilated than urban-urban migrants.