Abstract: The socialized service of agricultural machinery is of great significance for promoting green food production and building a modern agricultural system. Based on the panel data of 30 provinces in China from 2010 to 2020, a multi-dimensional indicator system of agricultural machinery socialized service level was constructed, and the SBM undesirable model was used to measure the green production efficiency of grain. The spatial Dubin model was used to empirically analyze the spatial spillover effect, mechanism and boundary of agricultural machinery socialized service on the green production efficiency of grain. The research shows that in the time series dimension, the green production efficiency of grain shows a steady upward trend from 2010 to 2020. In the spatial dimension, the degree of agglomeration of grain green production efficiency in each province has been continuously strengthened. The socialized service of agricultural machinery can promote the green production efficiency of grain in this region, and play a positive spillover role to neighboring areas. Moreover, the socialized service of agricultural machinery can realize the improvement of green production efficiency of grain through the interaction of agricultural land scale operation and rural finance. The effective distance of the spatial spillover of agricultural machinery socialized services to the green production efficiency of grain is 600 km, beyond which it will be limited by the geographical distance and no longer significant. In view of this, we should steadily improve the socialized service level of agricultural machinery, improve the coordination and cooperation mechanism between regions, promote the large-scale operation of agricultural land, and improve the level of rural financial development.