The pulsed laser ablates the material to form a surface micro-nano structure. In order to enhance the quality and efficiency of surface repair, the cold spray deposition process after pulse laser etching pretreatment was studied. Firstly, based on the pulsed laser action process and experimental observation results, simulation models between single/multiple particles and substrate were established. Secondly, thermal-structure coupling algorithm is used to carry out numerical simulation of the collision process between particle and substrate with surface micro-nano structures, and the effect of pulsed laser etching on the deposition process of cold sprayed materials is studied. Finally, the material deposition mechanism during the pulse laser assisted cold spray repair process was analyzed. The results show that the micro-nano structures formed by etching makes the temperature distribution in the collision area more uniform, and the deformation is more complicated, especially the deformation of the collision center area is significantly improved. When the collision position is the peak of the micro-nano structure, the strain and temperature rise are the largest, and the valley is the smallest. The deposition mechanism of pulse laser assisted cold spray is mechanical-physical bonding at plastic jet area and metallurgical welding in laser melting zone.smallest. The deposition mechanism of pulse laser assisted cold spray is mechanical-physical bonding at plastic jet area and metallurgical welding in laser melting zone.