The producer services is an important driving force for empowering high-quality development. In the context of population aging, how to promote the agglomeration development of producer services is an important issue that China needs to solve in the stage of high-quality development. Based on the analysis of the impact mechanism of population aging on the spatial agglomeration of producer services, this paper empirically analyzes the impact of population aging on the spatial agglomeration of producer services using the panel data of China’s provinces from 2003 to 2019. The conclusion shows that the aging population in each province has promoted the spatial agglomeration of producer services between cities within the province. The population aging mainly increases the level of knowledge spillover between enterprises through human capital effect and information dissemination effect, thereby enhancing the spatial agglomeration of producer services, and mainly has a negative impact on the spatial agglomeration of producer services by reducing the supply level of labor and reducing the matching opportunities and quality between labor and enterprises. Overall, the net effect of population aging on spatial agglomeration of producer services is positive. Therefore, the government should comply with the trend of population aging, adhere to the market-oriented principle to promote the agglomeration development of producer services. At the same time, it should also strengthen policy guidance to avoid the negative impact of population aging through labor supply effect.