On the basis of Summarizing theories related to public goods, with the aid of trend curve of China's annual grain yield from 1978 to 2010, in combination with grain policies at that time, empirical analysis is carried out on institution as key factor influencing the farmers' enthusiasm, showing that there is highly positive correlation between institutional change and grain production. In order to raise farmers' production enthusiasm and ensure the national grain security, this paper puts forward appropriate countermeasure systems from the point of view of innovating grain production policies. The countermeasure systems include: firstly, innovate agricultural operation institution; secondly, improve agricultural personnel cultivation mechanism; thirdly, complete financial investment system; fourthly, set up grain security protection system; and finally, build risk support system.