Abstract: In order to improve the accuracy of the hydraulic design of drip irrigation laterals, a finite element method for calculating the energy loss and irrigation uniformity of thin-wall drip irrigation pipes was proposed. The local head loss was determined by the structure of the emitter, working pressure head and lateral wall thickness. The friction head loss along the lateral was calculated by the modified Darcy-Weisbach formula. A computer program was developed to analyze the head loss and uniformity of different drip irrigation pipes. In addition, the results of the proposed method were compared with those of the recommended calculation method in our country′s Technical Specifications for Micro-irrigation Engineering（GB/T 50485—2009）. The results show that the total head loss h_w of the pipeline increases with the increase of the inlet pressure head. With the increase of the emitter spacing, the emitter number and total head loss h_w decrease under the same pressure head and lateral length. The h_w calculated by the technical specifications is much lower than that calculated by this model, when the emitter spacing is large. When the emitter spacing is small, the results of the recommended method are appropriate. When the working pressure is low, the lateral wall thickness has an obvious impact on the irrigation uniformity, which decreases with the increase in wall thickness and the corresponding decrease in cross section. When the emitter nominal flow rate is low, compared with the pressure head, the wall thickness has a low influence on the design maximum lateral length.