At present，it has become an important task for the work of agriculture，rural areas and farmers to curb the “non-agricultural” of cultivated land，prevent the “non grain” and effectively ensure food security. The overall situation of grain production in Jiangsu Province is good，but the inducement of “non grain” still exists，and there is still a possible risk of the spread of non grain，which will impact the basic self-sufficiency level of grain in the province in the future. The survey found that the main causes of “non grain” are ideological cognitive deviation on cultivated land protection and food security，weak policy binding force，insufficient support，difficult balance of interests among local governments，and lack of expected income incentive for economic subjects. To prevent “non grain”，we need to fully grasp the dual attributes of “quasi public goods” and “private goods” of grain products，and comprehensively use policy，economic and other measures. First，improve the level of understanding and rationally treat the “non-agricultural” and “non grain” behaviors differently；Second，further refine the grain production zoning and improve the monitoring and early warning mechanism；Third，implement local production responsibility and improve regional compensation mechanism；Fourth，improve the modernization and large-scale operation level of grain production and enhance the accuracy of direct grain subsidies.