Leisure and recreation have a profound influence on the social assimilation of migrants in urban areas. Different from previous studies,we focus on the social assimilation of migrants by taking an investigation into their leisure and recreation life. With the rapid urbanization accelerated by China's Reform and Opening-up Policy, migrants account for an increasing proportion of the resident population in cities, especially in those large ones. Social assimilation of migrants has commanded more and more attention. Urban parks are not only visited by local citizens but also favored by migrants. Leisure and recreation in urban parks provide an opportunity for migrants to get assimilated into the urban society. Like local residents, migrants are also confronted with the problem of crowding in urban parks, especially in those well-known ones. The problem of crowding has a direct constraint on the leisure and recreation behaviors of migrants. Perceived crowding is a subjective and negative evaluation of density. It is a stress caused by the interaction of people and the environment. Coping strategies should be employed to deal with the stress. The Perceived Crowding-Coping Model is used to study the coping strategies that the recreationists used to deal with perceived crowding. A comparative analysis is to be taken to test the models of urban citizens and migrants in urban parks around the West Lake in Hangzhou.It is found that local citizens visit urban parks around the West Lake more frequently than migrants. More than half of the migrants in parks report that they are college graduates(54%). Most of the migrants in the urban parks around the West Lake are young recreationists. Migrants in the 21 to 30 age group amount to 74. 1%. The difference in monthly household income between local recreationists and migrants is significant. Among the local citizens, recreationists with a monthly household income between 10 000 and 19 999 yuan account for 27. 7% while 21. 6% of the migrant participants report that their monthly household incomes are between 4 000 and 5 999 yuan. The results of CFA(Confirmatory Factor Analysis)show that absolute displacement, temporal substitution, activity substitution, resource substitution, product shift and direct action are the main coping strategies employed by recreationists in the urban parks around the West Lake to deal with crowdedness. Although there are no significant differences in perceived crowding between local citizens and migrants, they exist in their coping mechanisms. Migrants tend to choose the single coping strategy — absolute displacement, i. e. no more visit or leaving the parks immediately. Local citizens prefer some multiple coping strategies to deal with the problem of crowdedness in urban parks. Temporal substitution might be employed to avoid crowding in the peak time. Local citizens have more choices in leisure/recreation activities and resources to deal with the problem. Cognitive adaptation is used by local recreationists to persuade themselves to accept the situation. Both local citizens and migrants feel reluctant to take direct actions to solve the crowding problem. Since the satisfaction of leisure/recreation experience in urban parks is important for migrants' assimilation into the urban society, managers or administrators of urban parks could help migrants to deal with the crowding problem in urban parks by the promotion of leisure/recreation concepts, the rearrangement of leisure/recreation resources/activities, and the guidance of leisure/recreation behaviors.