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In order to obtain the optimum geometrical parameters for improving the anti-clogging performance of labyrinth flow path of drip emitter,16 kinds of flow paths were designed according to the structural parameters such as angle, height, upper base, offset and width. An Eulerian-Lagrange liquid-solid multiphase turbulence model combined with the kinetic theory of granular flow was used to carry out simulation based on coupled CFD-DEM water-sand two-phase flow in drip irrigation emitter, which analyzed the pass rate of sand group, the percentage decrease in speed of sand, the movement and distribution regulars and force and so on. The result indicated that the clogging performance of labyrinth channel could be expressed by the pass rate of sand. There existed a negative relationship between the pass rate and percentage drop of sand group speed . The speed descending of sand movement was the key factor that affected the sand pass rate in labyrinth channel. The angle and width were the main structural parameters of flow passage that affected the water flow characteristics. The speed of sand particles depended on the flow characteristics of the flow channel, and the angle had a significant influence on sand speed. Sand was always drawn by drag force from water flow in the optimum structure. Most of the sand ran in the mainstream area, so they maintained high movement speed. Little sand lost kinetic energy, thereby it reduced the blocking probability. This method was applied to analyze movement and distribution of sand group, understand the movement of sand from micro-view perspective, and it had become an efficient technique in structural design of labyrinth channel.