The mill with the inter-roller plate is a new type of mill developed at the Bydgoszcz University of Science and Technology. The design of the mill allows to control the grinding gap between the rollers and the plate and thus the particle size distribution of the comminution product. Mill geometrical features, such as gap between the roller and the plate, rollers texture, rollers size and working parameters (for instance rotational speed) play a crucial role in determination of the processing capacity, energy usage and product particle size distribution during comminution. In this study, we investigate the possibility of discrete element method (DEM) simulation to evaluate and optimize minerals comminution process using the mill with the inter-roller plate. In the simulation the selected geometrical features were changed and the power, the particle size distribution, the throughput and the stress distribution on the mill equipment were investigated,. The results showed that the mills characteristics influence its performance and the DEM simulation can be used to evaluate and optimize the design features of the mill equipment.