Abstract: As the core driving force for optimizing agricultural production systems, agricultural new quality productive forces transform traditional farming practices through technological innovation and model upgrading, playing a key role in advancing the green and low-carbon development of agriculture. Based on panel data from 30 provinces in China from 2013 to 2022, this study employs a two-way fixed effects model to investigate the direct impact of agricultural new quality productive forces on agricultural carbon emission intensity, and further utilizes mediating and quadratic term models to analyze its effects and underlying mechanisms. The study found that agricultural new quality productive forces significantly reduce agricultural carbon emission intensity. Heterogeneity analysis shows that compared with other regions, the carbon emission reduction effect is more significant in non-major grain-producing areas and areas with high agricultural technology investment. In addition, mechanism tests indicate that agricultural land productivity is an important mediating pathway through which agricultural new quality productive forces reduce agricultural carbon emissions; there is a U-shaped non-linear relationship between agricultural new-quality productive forces and agricultural carbon emissions. When the index of agricultural new quality productive forces exceeds 0.58, the carbon emission intensity may rebound. The research conclusions provide important insights for optimizing the development strategies of agricultural new-quality productive forces and formulating targeted differentiated agricultural carbon emission reduction policies, which are conducive to the sustainable development of society.