In view of the relationship between the wave propagation law and the channel，this paper studies the influence of wave incident angle and grid side length of channels on wave propagation law based on the wave numerical model.The results show that after channel dredging，when the wave incident angle is 15°，the maximum change rate of wave height between the wave-facing side and the back side of the channel can reach 6.6%，and when the minimum grid side length of the channel is 0.12 relative to the width of the channel slope，the channel slope can be simulated accurately，and numerical simulation is quick.