The continuous promotion of farmers' income is an important basis for common prosperity, and the financial support for agriculture policy, as an important institutional guarantee for the realization of a powerful agricultural country and Chinese path to modernization, plays a key role in improving agricultural income. This article is based on data from 30 provinces and cities in China from 2007 to 2021, and constructs a panel econometric model to empirically analyze the impact of fiscal support for agriculture on farmers' income. The analysis results indicate that fiscal support for agriculture expenditure can promote the growth of farmers' income, but the effect intensity is relatively weak compared to other variables. The income of farmers is comprehensively influenced by various factors, including the level of economic development, urbanization, rural industrial structure, and agricultural mechanization. However, the rural industrial structure has a negative impact on farmers' income growth. Therefore, in the future, China still needs to increase financial support for agriculture, improve the use efficiency of financial support for agriculture funds, promote the process of new urbanization, accelerate the development of agricultural modernization, optimize the industrial structure, inject new momentum into rural revitalization, and promote the realization of common prosperity.