Computational fluid dynamics software Fluent 6.3 was adopted to simulate the flow of triangle circulation drip irrigation emitters, the models were built by 3-D software Pro/E. By analyzing the flow hydraulic performance and the turbulence characteristics of emitters, the mechanism of internal turbulent flow was revealed, the flow structure was optimized. Based on the simulation results, by changing the shape and position of the external and the small internal triangular, a new type of triangle circulation drip irrigation emitter with flow index of less than 0.5 was got, velocity distribution was uniform, within the allowable flow range and excellent anti-clogging performance. A theoretical basis for the triangle circulation emitters structure design and quantitative analysis was provided. 