Abstract: Taking the unexpected output into account and stripping the impact of the external environment, the improved three-stage DEA model was used to calculate the national agricultural production efficiency from 2015 to 2019, and the regional differentiation was analyzed. The results showed that the external environmental factors had a significant impact on agricultural production efficiency. The per capita disposable income of farmers improved the allocation of land and irrigation factors, the urbanization level improved the operation efficiency of machinery, labor and chemical fertilizer, the local financial expenditure on agriculture, forestry and water affairs was not conducive to agricultural production efficiency, the improvement of education level promoted farmers’ ability to control machinery, land and other factors, and the development of industrialization drove the operation of agricultural machinery. After stripping the external environmental interference, the national agricultural production efficiency had changed significantly. The average comprehensive efficiency in five years had increased by 0.07, the pure technical efficiency had increased by 0.05 and the scale efficiency had decreased by 0.01. In the third stage, the national agricultural production efficiency was divided into four types. The efficiency “high high type” in the middle was mostly and evenly distributed; the east was second, but there was a slight imbalance in development, and some areas had been “low low type” for a long time; the efficiency distribution in the west was extremely uneven, and the polarization between “high high type” and “low low type” was serious.Based on this, the strategies were put forward to promote the agricultural construction from the perspectives of external environment and regional characteristics.

Key words: agricultural production efficiency, unexpected output, external environment, three-stage DEA model, SBM model