Abstract: The total power of agricultural machinery in each province （city） year was taken as the explanatory variable, the grain sown area was used as the intermediary variable, the grain output was used as the explained variable, the proportion of rural population, amount of agricultural fertilizer application, plastic film use, effective irrigation area, amount of agricultural diesel use and expenses on agriculture, water conservance and forestry were selected as control variables, and the national interprovincial panel data from 2007 to 2019 were studied using SPSS 23.0 software. The results showed that the total power of agricultural machinery and the grain sown area had significant positive effects on the total grain output; the grain sown area played a complete intermediary role between the total power of agricultural machinery and the grain yield. Accordingly, countermeasures and suggestions were put forward to improve the level of agricultural mechanization and its application effect, promote the expansion of grain planting area, improve grain production efficiency, increase grain output and improve quality and efficiency through diversified expansion of innovation channels.

Key words: agricultural mechanization level, grain sown area, grain yield, intermediary effect, panel data analysis