The stirred media mill with pin-type rotor structure is one of the important equipment for manufacturing superfine powder. The CFD-DEM method is used to simulate the solid and liquid flow in the stirred mill. The velocity, collision and energy in the grinding chamber were analysed. The results show that the velocity gradient near the wall of the cylinder and agitator is large, and the velocity gradient near the cover plate on both sides is small, and the distribution of solid particles with high velocity in the grinding chamber is small; the particle distribution in the grinding cavity is not uniform, showing a tendency to pile up to the cover plate on both sides; the total energy per particle in the area near the agitator is much higher than that of the cover plate area on both sides, and the area near the agitator is the effective grinding area.