Abstract: The invention relates to a kit for preparing a mixture of a natural or synthetic bone filler material with blood or physiological serum. According to the invention, the kit comprises a stand, a cup, and a tube for containing the mixture, the tube being open at both ends, the stand having receiver means for receiving one end of the tube in a vertical position, and the cup including an orifice in its center and communicating with a sleeve for releasable assembly on the other end of the tube.