Background <p>Health inequality is a global issue, with a particularly significant impact on older adults. In China, differences in the urban administrative hierarchy may lead to uneven allocation of public resources, resulting in the concentration of public resources in cities with higher administrative hierarchies and, consequently, health inequality among older adults. Therefore, this study aims to explore the relationship between urban administrative hierarchies and older adults’ subjective physical and mental health, while also analyzing the role of resource allocation mechanisms in shaping this dynamic.</p> Methods <p>This study utilizes data from the China Family Panel Studies, the China City Statistical Yearbook, and the China Urban Construction Statistical Yearbook, employing a multi-dimensional fixed effects model, incorporating province, individual, and time variables, to evaluate the impact of the urban administrative hierarchy on the subjective physical and mental health inequality of older adults. The study considers medical and environmental resources as potential mediating variables and explores the moderating role of marketization.</p> Results <p>The findings reveal a positive correlation between the urban administrative hierarchy and older adults’ subjective physical and mental health, with those in cities with higher administrative hierarchies enjoying higher quality of life and subjective health levels. This is primarily due to cities with higher administrative hierarchies owning medical and environmental resources. Furthermore, the level of marketization has a positive moderating effect on the positive relationship between urban administrative hierarchy and older adults’ mental health, but has no significant impact on physical health. Heterogeneity analysis by region and age indicates that the impact of the urban administrative hierarchy on the physical and mental health of older adults is more pronounced in economically less developed regions and among younger elderly individuals.</p> Conclusion <p>The study highlights the inequalities in the subjective physical and mental health of older adults across cities with different administrative hierarchies in China. By providing more resources, cities with higher administrative hierarchies can significantly improve older adults’ life quality and subjective health. Meanwhile, marketization further strengthens the positive impact of urban administrative hierarchy on mental health. By introducing the urban administrative hierarchy as a macro-level political system into the study of individual health disparities, this research not only expands the analytical perspective on health inequalities among older adults, but also provides empirical support for understanding the current trends in elderly migration for retirement. Moreover, it offers valuable insights for global aging governance and promoting health equity.</p>