Accurately assessing the performance of low-carbon agricultural development and identifying its spatiotemporal evolution characteristics and trends are essential for scientifically formulating low-carbon agricultural development policies and achieving harmonious progress between agricultural economic growth and ecological environment.Based on the SBM function and GML index，this study calculates the agricultural total factor carbon productivity （ATFCP） of 269 cities in China from 1999 to 2021.Then，Dagum’s Gini coefficient is used to characterize its spatial differentiation characteristics， and finally，spatial panel mode is employed to test its convergence.The empirical results indicate that China’s ATFCP an overall upward trend,primarily driven by technological progress.The regional differences in ATFCP have been expanding year by year，mainly due to inter-provincial differences （58.10%），folowed by hypervariable density（38.15%），with intra-provincial differences being the smallest at only 3.75%.There is no convergence in ATFCP,but absolute convergence and conditional convergence exist,along with spatial spillover effects.That is，the growth of the ATFCP in one area can accelerate the improvement of ATFCP in surrounding regions.This finding holds true even after robustness checks, such as adjusting the sample period，changing time intervals and altering spatial weight matrices.