Enhancing the mental health of rural migrant workers and promoting their urban integration are essential for advancing the new urbanization. Based on a micro-survey dataset of 2 427 migrant workers, this study constructs a comprehensive set of indicators and employs factor analysis, OLS regression, and quantile regression methods to investigate the impact of mental health on the urban integration of migrant workers. The results indicate that a positive mental state effectively promotes the urban integration of migrant workers, while a negative mental state hinders it. The influence of mental health on urban integration varies significantly across different quantiles. Additionally, control variables such as age, education level, marital status, parental migration status, and the number of family members working outside have significant effects on the urban integration of migrant workers. Based on the research findings, it is suggested that relevant departments should pay attention to and prioritize the mental health issues of migrant workers and take measures to safeguard and improve their mental health during the process of urban integration. Furthermore, tailored interventions should be developed to enhance the mental health of migrant workers with different degrees of integration, thus helping them better integrate into urban life.