Based on ArcGIS software, this paper studies the spatial layout characteristics of pension institutions in 31 provinces and cities (excluding Hong Kong, Macao and Taiwan) from the perspective of fairness and balance by using the spatial analysis method, explores the overall development process and evolution characteristics of pension institutions in China, and uses a modified two-step floating catchment area method to analyze the spatial accessibility of the pension institutions in each county. The research shows: The development process of pension institutions can be divided into four stages: the budding period (1949—1977), the growth period (1978—1998), the standard period (1999—2008), and the construction period (2009—2020). Each stage has different distribution characteristics. The overall regional distribution of pension institutions is quite different, mainly concentrated in the eastern and central regions, but the western region is relatively scattered, and the supply level has not yet reached the expected target value. The spatial distribution of pension institutions has multiple clustering cores, and the overall layout is in a triangular distribution, with the density gradually decreasing from the clustering center to the surrounding areas. It is more effective to divide the effective service radius by scale to evaluate the spatial accessibility of pension institutions. The accessibility of southeastern region is significantly better than that of the northwest region. The northwest region is mostly low-value accessibility areas. The resource allocation of pension institutions needs to be further improved.