Carbon emissions reduction and carbon sequestration in the field of agricultural machinery and equipment is an important component of China's goal of achieving green and low‑carbon agricultural development. The financial and taxation system is an important support for promoting agricultural mechanization and green and low‑carbon development, and needs to further play its functional role. In order  to explore the dynamic relationship between agricultural mechanization, fiscal expenditure and agricultural carbon emission, based on China's 2000 to 2022 data, the dynamic relationship between agricultural mechanization, fiscal expenditure and agricultural carbon emission was studied by constructing a VAR model, using pulse response analysis and variance decomposition. The results showed that agricultural mechanization was the Granger cause of fiscal expenditure and agricultural carbon emission, and there was a two‑way Granger causal relationship between fiscal expenditure and agricultural carbon emission. The results of variance decomposition showed that the contribution rates of agricultural mechanization and fiscal expenditure on agricultural carbon emissions gradually increased in the second and later periods, reached 14.06% and 22.36% respectively, indicating that agricultural mechanization and fiscal expenditure had strong effects on promoting the reduction of  agricultural carbon emissions.