Abstract: In the past, the research of optimal allocation of irrigation of water resources was focused on the economic benefits. It had ignored the social and ecological benefits, and was not suitable for the extremely fragile and arid areas of northwest. Based on the idea of the original optimization model, this paper proposed the virtual water strategy optimization model of regional agricultural structure by setting up the rigidity constraints for local production, living conditions and water demanding to environmental improvement. Then, Minqin County was taken as an example. The results showed that the food crop acreage decreased, the vegetable crop area increased significantly with the coefficient of virtual water trade increasing. Its economic efficiency and water-use efficiency were markedly improved, and the food dependency also would be gradually increased. The trading foundation and water-saving technology could ensure the food security. Saved valuable water resource was conducive to the improvement of the ecological environment in drought region. Solving the optimization program will be helpful to develop a rational and effective policy of industrial restructuring.