Based on the quasi-natural experiment in the National Poverty Alleviation and Reform Pilot Zone in Lishui, Zhejiang Province in 2013, and the panel data of 58 counties in Zhejiang Province from 2007 to 2020, we mainly use the Difference-in-Differences fixed effect identification method to observe, understand and evaluate the effect and mechanism of the Pilot Zone on the supply level of local basic public services. The results show that the Pilot Zone has promoted the local per capita expenditure on basic public services to increase by about 750 yuan, and the conclusions are still valid after a series of robustness tests in different form. From the perspective of dynamic effect, the Pilot Zone has a significant long-term impact on improving the supply level of local basic public services. Further analysis of the mechanism shows that the establishment of the Pilot Zone has prompted local governments to bear greater pressure on fiscal revenue and expenditure, and to make use of tax efforts, at the same time, through the adjustment of the financial budget structure, it can achieve the goal of improving the supply level of basic public services. In addition, the different characteristics of different areas within the Pilot Zone have a certain impact on the different types of basic public service supply. Lishui is a microcosm of a Pilot Zone for anti-poverty reform. This paper will helpful to provide a feedback perspective for policy makers, and it is also helpful for us to find a new way to construct the moderate social welfare system in China.