Abstract: In order to realize the relationship between the rural floating population and the regional grain production, and protect the regional grain security, the article uses the empirical analysis method to study the grain production and the rural floating population in Anhui province and Shanghai City. The results showed that, the increase of the rural floating population outflow did not lead to regional food production to reduce, and the increase of the rural floating population inflows would not lead to regional food production increases. It meant that there was a reverse variation relationship between the rural floating population and regional grain production. On the whole, the flow of the rural floating population can promote regional grain production. In order to protect the regional grain security, according to two conditions of rural floating population outflow and inflow, some advises are proposed separately to lead rural floating population and achieve the increase of regional grain production.