Abstract: With the rapid transformation of rural land，large-scale，crop planting structure has changed accordingly，the proportion of grain area decreased，the proportion of cash crops gradually increased，agricultural land distribution showed“ non-grain” trend. It is very necessary and urgent to study the change of farmland circulation and planting structure in Ningxia to ensure the supply of regional food security. This paper analyzed the present situation and non - grain reason of farmland circulation in Ningxia，and then put forward to the incentive and restraint mechanism of establishing farmland circulation guarantee food security.