China's charitable organizations are playing an important role in the realization of common prosperity in the new era. This paper makes an in-depth study of the impact of financial expenditure level on non-profit organizations' public welfare expenditure scale, which is of great significance for understanding the relationship between government governance and non-profit organizations' public goods supply and promoting the sharing of development achievements. This paper selects the annual panel data of China's charitable foundations from 2009 to 2018 to test the logic of local government financial expenditures on charitable organizations' charitable expenditures. The findings are as follows: (1) The moderate expansion of government expenditure significantly promoted the improvement of the level of public welfare expenditure of foundations, and the results remained robust after a series of robustness tests such as substitution variables and processing outliers; (2) The positive incentive effect of financial expenditure on foundation public welfare expenditure has regional heterogeneity, that is, it significantly promotes the development of charity in central and western China, but not in eastern China; (3) Foundations with different fundraising types respond differently to the increase in financial expenditure. Compared with private foundations, public foundations are more likely to "respond" to the government's social and economic development orientation, and fiscal expenditure has a stronger incentive effect; (4) The impact mechanism test shows that fiscal expenditure increases the donation income of foundations by encouraging social charitable donation, and thus has a significant positive effect on public welfare expenditure.