The work aims to explore the effect of working parameters of the leather grinding system of the roller mill on the process efficiency, and optimize the working parameters of the grinding roller in the 1B grinding process. The grinding process of the grinding roller was simulated and analyzed using Dem discrete element software. The effects of four factors, namely tooth angle, front angle, rolling distance, and spacing between feeding points, on the powder extraction rate and power consumption were used as variables for analysis. Orthogonal tests and matrix analysis were used to comprehensively evaluate the numerical simulation results. The optimal parameter combination scheme for 1B grinding powder process was tooth angle γ=85°, front angle α=25°, rolling distance d=1.5 mm, spacing between blanking points b=0 mm. This article provides a method reference for the simulation analysis of the grinding process of the roller mill, and has certain guiding significance for the optimization of working parameters of the roller mill.