Abstract: The invention relates to a material bed roller mill with a fixed roller and a floating roller which between them form a grinding gap and a hydraulic-pneumatic spring system which presses the floating roller in the direction of the fixed roller and contains at least one hydraulic working cylinder and a working pneumatic spring which cooperates therewith for each side of the floating roller. The spring container of each working pneumatic spring is divided by two movable pistons into a central gas filling chamber and two opposing hydraulic fluid chambers, and a stroke measuring device is associated with one piston for the preliminary filling pressure of the hydraulic fluid. In this way it is possible to reset the grinding force during operation by means of the hydraulic pressure with the same pneumatic spring characteristic on both sides of the floating roller.