Abstract: In pushing forward the agriculture economic reform and preferential tax framework dynamic evolution, the impact of tax preferential policies on agricultural scientific and technological innovation is particularly critical. The research aims to further validate the influence of tax preferential policies on the technological innovation of agricultural enterprises. We analyzed the data of 40 agricultural leading enterprises and cities based on Poisson regression, fractional regression and mediation effect. The results showed that, tax preferential policies played a significant role in promoting scientific and technological innovation, but had a weakening effect on R&D investment, and had no significant incentive for human input. At present, the tax preferential policies have not formed an effective incentive system for agricultural science and technology innovation. The empirical analysis has certain practical applicability, and can provide a quantitative reference for the formulation of preferential tax policies and the innovation of agricultural science and technology.