Abstract: A roller mill includes a shell provided with a feed port and a discharge port; a main shaft inserted in the shell and rotatable in the shell; a drive device drivingly connected to the main shaft a holder mounted on the main shaft two or more than two grinding rollers, each of the grinding rollers mounted on the holder and rotatable around its own axis; and a grinding disk fixedly mounted in the shell at a position opposite to the multiple grinding rollers. The roller mill further includes an axial position adjustment device connected to the main shaft and configured to drive the main shaft to move axially to adjust a position of the main shaft.