Study On The Mechanism For The Effect Of Agricultural Mechinery Purchase Allowance In Main Grain-producing Area

China is a developing agricultural country, arable land accounts for only 10% of the world's population accounts for 22% of the world, over one billion people's food issue has always been of paramount importance. China's government in 2001 published "China's grain problem," White Paper made it clear that China can achieve on its own basic self-sufficiency in food, this is our government to resolve the issue of food security the basic principle. Attaches great importance to protecting and improving the comprehensive grain production capacity, establish a stable commodity grain production base, with China's national conditions and the establishment of the socialist market economy of food security system to ensure food supply and demand balance, which is the Chinese government to resolve the issue of food security the basic principle of achieving food security is the goal of the total.Agriculture is a weak industry, is also highly of the special public welfare industries. Both developed and developing countries, agriculture has always been subject to government intervention and support. Financial support is government regulation and control and protection of agriculture as the core measures. For a long time, the development of China's agricultural mechanization to some extent is constrained by low income of peasants; farmers are on the urgent needs of agricultural mechanization, but lack of effective purchasing power. Therefore, accelerating the development of agricultural mechanization, policy support is the key. Agricultural machinery purchase allowance aims at improving agricultural equipment structure, improving agricultural mechanization, and enhancing comprehensive agricultural production capacity. The development of modern agriculture further mobilizes farmers to buy and use agricultural mechanization enthusiasm. The development of agricultural mechanization promotes modernization of agriculture, agricultural and rural fast economic development. In this paper, the use of domestic and international agricultural policy and changes in the environment based in Henan Province, along the relevant scholars study the agricultural policy ideas, collect data, field surveys, carried out research papers. The use of literature collection, classification summary, comparative analysis and quantitative assessment method of development of domestic and international agricultural research and development. With the analysis software, using the survey analysis and the typical combination of macro-and micro-study of research method of combining the data and information collation, analysis, research.This article begins with agricultural machinery purchase allowance, and then uses comparative analysis, trend analysis methods to analyze the effect and mechanisms of the policy, and then further uses economic theory related to the purchase of farm machinery subsidies to analyze. The main objective is, through the purchase of agricultural machinery to China's subsidy policies and mechanisms of the effect of the study and explores the effects of their policies to achieve and improve. Research shows that the purchase of farm machinery subsidy policy of social benefits far greater than economic benefits. Finally, how to improve China's policy of subsidizing the purchase of agricultural machinery and improve the efficiency of the corresponding policy are recommended.