At present, air pollution remains a serious environmental issue with extensive attention in China. It may not only cause population outflow but also poses significant threats to residents’ health. Therefore, it has become an imperative initiative to explore the impact of air pollution on the residents’ health. In this paper, we map the spatial distribution of air pollution, population migration, and residents’ health between 2010 and 2020 based on panel data from 31 Chinese provinces. Theoretical analysis and empirical tests are then carried out to investigate the intrinsic logical relationships between the three. The research findings demonstrate the following: (1) Air pollution not only has a direct negative impact on residents’ health, but it also has an indirect impact on residents’ health through the mediating effect of population migration. (2) Air pollution has a significant negative spatial spillover effect on residents’ health, and neighboring residents are at greater health risk of being exposed to air pollution than local residents. (3) Economic development, environmental regulation, and their interaction term exhibit a single threshold effect on the health risk of air pollution. (4) From the perspective of regional heterogeneity, we find that the health risk of air pollution is greater in northern China and the southeast of the Hu Line. This paper provides valuable insights for promoting the implementation of the grand strategies of “Beautiful China” and “Healthy China.”