Abstract: In order to reveal the collision-induced fragmentation mechanism and law of coarse particles during hydraulic transport of deep sea mining, thus optimizing the transport parameters. In this work, the random geometric numerical reconstruction of coarse particles was carried out based on a Python program, and then the whole process simulation of the collision-induced fragmentation of particle was carried out. The effects of particle impact velocity, impact angle, and particle size on particle fragmentation were studied by the validated numerical model, and the typical particle fracture morphology and mass loss rate were determined. The simulation results show that, the brittle cracking model based on Type I fracture energy can simulate the collision-induced fragmentation process of particle accurately; and the particle fragmentation was mainly influences by impact velocity, and particles are more likely to fragment at higher incidence angles, fine grain are less likely to fragment, while larger sizes may fragment even at low impact velocity.