Abstract: The present invention relates to an arrangement for the manufacture of bone cement by mixing together its constituent components comprising a mixing cylinder (1) in the form of a tube with a bottom (2) and a lid (3) and inside the mixing cylinder an axially movable agitator (4). The agitator consists of a piston-like agitator disc (4a), which is perforated by channels (4a1), through which the components of the bone cement are caused to flow during the mixing procedure and an agitator rod (4b) resembling a piston rod operatively connected to the agitator disc (4a) and supported in the lid (3) in such a way that it is free to slide. The invention is characterized in that the agitator rod (4b) has an axial channel (4b1), which is closed off at the agitator disc (4a) in such a way that it is capable of being opened.