A pelletizing press for producing pellets from material to be pressed, preferably from biomass, for use as fuel in fire places, wherein the biomass consists of cellulosic and/or lignocellulosic fibers, chips or shreds. In the pelletizing press, a dispersion chamber is formed by at least one die having a plurality of bores for pressing the biomass and at least by a lateral wall, and at least one roller rolling on a rolling surface of the die is arranged in the dispersion chamber. A pelletizing press of this method for producing pellets enables the formation of a dispersion chamber that, by means of at least one lateral wall, is as compact and sealed as possible relative to the prior art. At least two lateral wall parts are arranged to form a lateral wall; at least the first lateral wall part is arranged to be movable in relation to the second lateral wall part for carrying out a relative movement.