The paper studies the effect and mechanism of China’s main grain price support policies on the increase of farmers’ income,based on the survey data of the National Rural Fixed Observation Point of the Ministry of Agriculture. Result shows that the positive effect of this policy on increasing farmers’ income in policy implementation provinces is limited,compared with other driving forces to increase farmers’ total income. In terms of influencing factors,the increase of farmers’ income is still mainly driven by regional economic development. Therefore,the current Price Support Policy should be further improved so as to enhance its effects in increasing farmers’ income. Under this premise,the issue of increasing farmers’ income should be integrated into the development of macro economy and the coordinated development of other industreis. Meanwhile,a long-term mechanism to increase farmers’ income should be set up with the coefforts of Price Support Policy,other policies and all the industries.