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 showed that the total head loss hw of the pipeline increased with the increase of the inlet pressure head. With the increase of the emitter spacing, the emitter number and total head loss hw decreased under the same pressure head and lateral length. The hw calculated by the technical specifications was much lower than that calculated by this model, when the emitter spacing was large. When the emitter spacing was small, the results of the recommended method were appropriate. When the working pressure was low, the lateral wall thickness had an obvious impact on the irrigation uniformity, which decreased with the increase in wall thickness and the corresponding decrease in cross section. When the emitter nominal flow rate was low, compared with the pressure head, the wall thickness had a low influence on the design maximum lateral length.