Abstract: According to experimental data in Libao experimental area of Huoquan Irrigation District from October 1996 to September 1999, the models of estimating crop water consumption and the relationships between crop yield and water consumption were established. Based on the models, the irrigation norms of high yield and water saving cultivation of winter wheat and summer maize were presented. Taking the continuous cropping of winter wheat and summer maize from October 1998 to September 1999 as an example, the water requirements and the water consuming processes of winter wheat and summer maize were analyzed. And the optimal distributing scheme of limited water resources in crop growing seasons was also suggested by the principle of dynamic programme.