Abstract: The wear problem on the windward surface at the inlet of each layer of the catalyst in the SCR reactor of the boiler flue gas denitrification device of the coal-fired generating unit is serious. The existing technology for the hardening treatment of the windward end of the catalyst is difficult to adapt to the changes in coal quality and the flue gas flow field. Based on wear-resistant ceramic materials, a rectangular porous ceramic-based anti-wear structure is designed. Numerical simulation of the ash and flue gas flow field in the catalyst channel after installing the anti-wear structure is carried out based on CFD simulation technology. The simulation results show that when the flue gas carrying ash particles enters the catalyst channel, the impact force and cutting force of the particles are the main causes of catalyst wear. The incident angle of the flue gas flow velocity is the main factor affecting the erosion rate. When the flue gas velocity increases from 3 m/s to 7 m/s, the erosion rate rises to 4.5×10⁻⁵ g/(m²·s). As the incident angle increases from15 degrees to 30 degrees, the wear of the channel side by the ash particles is stronger. Theanti-wear structure designed in this paper is conducive to the flow of flue gas, and there will be no ash accumulation phenomenon. It can extend the service life of the catalyst and optimize the operation environment of the catalyst.