Abstract: A device for mixing and discharging bone cement has a mixing cylinder which consists of two cylinder parts and in which an openworked mixing plunger can be moved axially. The lower cylinder part is sealed off by a discharging plunger. A separating plunger is arranged axially displaceably in the mixing cylinder between the mixing plunger and the discharging plunger, which separating plunger seals off the one cylinder part before the two cylinder parts are connected. The separating plunger has through-flow channels through which a liquid monomer can flow from the lower cylinder part to a pulverulent polymer in the upper cylinder part at the start of the mixing procedure.