Abstract: The cultivated land area and crop sown area in hilly and mountainous areas account for one third of the cultivated land area and the sown area of crops in the country, involving nearly 300 million agricultural population. Therefore, it is very important to study how to promote agricultural mechanization to realize agricultural power. Starting from the internal logic of agricultural mechanization development in hilly and mountainous areas, this paper compares and analyzes the cases of “farmland construction suitable for mechanization” and “adapting to land conditions with machinery ” and discusses the transformation power of agricultural mechanization from “adapting to land conditions with machinery” to “farmland construction suitable for mechanization”, calculates the subsidy standard of government support for “farmland construction suitable for mechanization” in combination with Hotelling model, and analyzes and interprets domestic and foreign cases. The research shows that the miniature agricultural machinery of “adapting to land conditions with machinery” has limited improvement of agricultural productivity, and the fundamental way for agricultural modernization and building agricultural power in hilly and mountainous areas lies in case of “farmland construction suitable for mechanization” to create land conditions for large power and high efficient agricultural machinery operation. In order to improve the willingness of agricultural operators to participate in the case of “farmland construction suitable for mechanization”, the government should adopt differentiated financial subsidies according to the machine conditions, reduce the input cost of agricultural operators of “farmland construction suitable for mechanization”, shorten the investment back to the fixed number of year. Among them, the subsidy standards for the slope below 2°, 2°-6°, 6°-15°are 15 000 yuan/hm~2, 30 000 yuan/hm~2 and 45 000 yuan/hm~2, respectively, the land principle for slope over 15°should be returned to forest and grass, and it is not appropriate to carry out high-cost mechanical transformation. In view of the agricultural mechanization experience and existing problems of “farmland construction suitable for mechanization” in hilly and mountainous areas at home and abroad, this paper puts forward the countermeasures and suggestions for actively and steadily promoting the case of “farmland construction suitable for mechanization” in the hilly and mountainous areas.