Abstract: Irrigation with plastic mulch is a new kind of surface irrigation method, it has both water-saving and yield-increasing effect. Plastic mulch affects motion laws of surface flow remarkably. So that it is requirement that study on irrigation technique for the irrigation with plastic mulch to increase irrigation uniformity and irrigation efficiency. This paper develops optimal mathematics model for the irrigation technique of the irrigation with plastic mulch based on numerical simulating to the motion of surface flow. Objective function of the optimal model is the irrigation uniformity, constraint conditions meet limits in irrigation norm, water depth on field surface, inlet unit-width discharge, and rate of plastic film hole. The optimal irrigation technique schemes for the irrigation with plastic mulch with holes are determined via calculating using data from the cotton experimental field at Wulanwusu Agrometeorological Station, Xinjiang.