China’s 14th Five-Year Plan emphasizes that it is necessary to speed up the urbanization of agricultural migrants and promote their comprehensive integration into cities and the high-quality development of new urbanization. Therefore, in order to promote migrant workers’ urbanization, it is particularly urgent to effectively enhance their willingness to stay in cities.

Based on the Chinese trade unions’ dual functions of safeguarding rights and maintaining stability, this paper discusses the impact of trade unions on migrant workers’ willingness to stay in cities and its mechanism from theoretical and empirical aspects by using trade-unions-related policy documents, media reports and CMDS（2017）. The results show that: First, trade unions can significantly increase the possibility of migrant workers’ willingness to stay in cities. Second, the impact of trade unions on migrant workers’ willingness to stay in cities is more significant for people with low-skilled jobs, in private enterprises, of low education and of the older generation. Third, trade unions can increase the possibility of migrant workers’ willingness to stay in cities by safeguarding their labor rights and interests and enhancing their sense of social integration.

The possible contributions are as follows: First, based on multiple source data, this paper uses textual analysis and empirical test to discuss the impact of trade unions on migrant workers’ willingness to stay in cities. Second, this paper proves that the dual functions of trade unions can play a role in coordination rather than conflict. Third, existing studies rarely discuss migrant workers’ willingness to stay in cities from the perspective of trade unions. This paper discusses migrant workers’ willingness to stay in cities from the perspective of trade unions, which not only enriches the literature in related research fields, but also provides new ideas for enhancing migrant workers’ willingness to stay in cities and accelerating the development of China’s new urbanization strategy.

In order to enhance migrant workers’ willingness to stay in cities, this paper suggests that: First, trade unions should attract more migrant workers to join it and also strengthen the protection of migrant workers’ labor rights. Second, trade unions should carry out various activities to promote communication, so as to enhance migrant workers’ sense of social integration. Third, trade unions should attach importance to migrant workers with low-skilled jobs, in private enterprises, of low education and of the older generation.