Social Integration for migrants is a combined process of increasing assimilation and reducing exclusion,and a process of coordinating expectation of migrants and acceptance of urban sector,and a process of developing counter relations and building social network among migrants and local people.The paper measures social integration degree of temporary migration in four dimensions,including identity recognition,expectation to city life,interaction with local residents and feeling of social attitudes from local citizens.Results show that various variables have different impact on different aspects of social integration.Based on a regression model,the paper tests three hypothesis on the factors associated with social integration of migrants:migrant individual and family characteristics are significantly associated with social integration;community participation and social capital significantly associated with social integration;and institutional arrangements significantly associated with social integration.In improving social integration of migrants,the paper argues for comprehensive policies addressing the variety and complexity of the process of social integration,including those towards natural integration and interventionary integration,active integration and interactive integration,and promoting a gradual and multidimensional integration process.