The exploitation and utilization of the water resource can be divided into three stages according to the transformation, development history,current situation and future tendency of the water resource of the piedmont plains in the arid Norhtwest Chiria. They are the exploitation and utilization stage of the surface water,the united exploitation and utilization stage of the underground and surface water as well as the economical use stage of the usable water resource. These stages reflect that the law and process of the use of water resource are related to the social and technical progress. Saving water is a main way in all the stages.However,the content of the economical use of water in the third stage is different from that in the first two stages,especially in respect of irrigation farming. It means a revolution of the traditional concept of water resource in the arid region. The net utilized water in the arid region is only 160×10⁸m3 at present according to investigation. It accounts for only 18% of the total water resource,which shows the exploitation and utilization of water resource is in an insufficient stage. The usable water can increase 91% if the first stage is completed and can increase 216% after the completion of the.second stage.Therefore,the potential is very great.