With the continuous growth of agricultural machinery holdings in various regions， the market capacity of trans-regional agricultural machinery services has been shrinking， and the localized agricultural machinery services are rapidly emerging. Based on the survey data from micro-level farmers in the North China Plain， this paper uses the stochastic frontier production function method in the form of super-efficiency production function to measure the technical efficiency of farmer’s grain planting， and empirically analyzes the impact of the “localization” of agricultural machinery service market on the technical efficiency and its mechanism. Results show that there is a certain degree of technical efficiency loss in grain production for farmers, mainly due to management errors. The “localization” of agricultural machinery service market， on the one hand， reduces the risk of yield reduction caused by delay in agricultural time， and improves the flexibility of factor allocation for farmers; on the other hand， it effectively constrains the moral hazard of machinery operators and enhances the quality of agricultural machinery operation,thereby promoting the improvement of technical efficiency in grain production for farmers. However， this positive incentive effect is gradually weakened with the expansion of farmers’ agricultural land-scale and the enhancement of off-farm employment. To enhance the incentive effect, it is necessary to build agricultural machinery service sharing platform and agricultural machinery service standards， and increase the flexibility of subsidies for agricultural machinery purchase.