In the Chinese economic system, agricultural small and medium-sized enterprises (SMEs) play a key role in promoting agricultural development. The problem of financing difficulties for agricultural SMEs has seriously constrained their economic development. The purpose of this paper is to explore the role of supply chain finance in solving the financing constraint problem of agricultural SMEs, which in turn affects the performance level of enterprises. By constructing a theoretical model and selecting the data in Chinese National Small and Medium Enterprises Stock Transfer System from 2011 to 2022 for mediation effect regression analysis, the results show that there is a stable positive correlation between supply chain finance index and return on net assets (β = 0.585, p < 0.05); there is a stable negative correlation between supply chain finance and financing constraints (β = – 0.216, p < 0.05); there is a stable negative correlation between financing constraints and return on net assets (β = –0.893, p < 0.001). This study examines the impact of supply chain finance on the performance of agricultural SMEs from the perspective that supply chain finance can alleviate financing constraints. The results of this study suggest to business stakeholders that agricultural SMEs can choose supply chain finance as a better choice of financial strategy, and the government can formulate corresponding policies to further develop preferential and supportive policies for supply chain finance.