Exploring the impact of conservation tillage machinery on green total factor productivity （GTFP） of grain can provide valuable insights for ensuring food security and achieving high-quality agricultural development. From the perspective of the “dual-carbon” goal, this study uses the SBM—GML index method to measure the GTFP of grain in 31 provinces of China from 2005 to 2021, and constructs a spatial Durbin model to quantitatively analyze the spatial spillover effect of conservation tillage machinery. The study finds that: during the sample period, the annual average GTFP of grain nationwide was 1.025, indicating an improvement in green grain production levels. While most regions showed a fluctuating upward trend in GTFP of grain, the degree of improvement remained modest. There are some differences in the changes of GTFP of grain across regions, with the green production levels of grain in plain areas being significantly higher than those in hilly and mountainous regions.  Conservation tillage machinery has a significant positive spatial spillover effect on GTFP of grain, which is mainly promoted by technological progress.  The impact of conservation tillage machinery on GTFP of grain varies depending on terrain and the grain functional zones. Therefore, in the future, we should focus on promoting conservation tillage technologies, improving the agricultural machinery subsidy policies, strengthening the construction of information exchange platforms for the supply and demand of agricultural machinery services, and advancing the innovation of agricultural science and technology to enhance the levels of agricultural machinery and equipment.

探讨保护性耕作机械对粮食绿色全要素生产率的影响，有助于为保障粮食安全和实现农业高质量发展提供借鉴。基于“双碳视角”，采用SBM—GML指数法测度2005—2021年31个省份粮食绿色全要素生产率，构建空间杜宾模型定量分析保护性耕作机械对粮食绿色全要素生产率的空间溢出效应。研究发现：样本期内，粮食绿色全要素生产率年均值为1.025，说明我国粮食绿色生产水平得到一定程度的改善；大多数地区粮食绿色全要素生产率呈波动上升趋势，但提升程度较小；地区间粮食绿色全要素生产率变动情况存在一定差异，平原地区的粮食绿色生产水平要明显优于丘陵山区。保护性耕作机械对粮食绿色全要素生产率具有显著的正向空间溢出效应，主要通过促进技术进步来提高粮食绿色全要素生产率。保护性耕作机械对粮食绿色全要素生产率的影响因地形和粮食功能区而异。因此，未来应加大保护性耕作技术推广力度，不断完善农机补贴政策，扎实推进农机服务供需信息交流平台建设并强化农业科技创新以提高农机装备水平。