The invention relates to a device for producing a spacer having a casting mold with at least one filling opening, a valve seat, which is connected to the casting mold, wherein the valve seat has an regionally closed head side with at least one first feed-through, a valve body which is mounted so as to be rotatable relative to the valve seat and which has a sealing face, wherein at least one second feed-through is arranged in the sealing face, wherein the valve seat and the valve body together form a valve, wherein the valve is reversibly transferable into an open position and a closed position by rotation of the valve body relative to the valve seat, wherein, in the open position of the valve, the at least one first feed-through of the valve seat and the at least one second feed-through of the valve body are located above one another at least in places and provide a permeable connection through the valve into the casting mold, wherein, in the closed position of the valve, the at least one first feed-through of the valve seat is covered by the sealing face of the valve body, wherein, in the closed position of the valve, the at least one filling opening of the casting mold is covered and wherein the valve is connected on the side remote from the casting mold to a port for liquid-tight connection of a bone cement cartridge or the valve has such a port. The invention also relates to a method for producing spacers using such a device.