A shoulder joint prosthesis has an at least two-pieced humeral head prosthesis, comprising a calotte, or a joint head (3) and a fixing body (5, 7). The latter comprises a fixing piece (15), for detachable connection of the calotte and a mounting section (21), for the at least cement-free anchoring of the fixing device in the bone. The fixing body is preferably of two-piece embodiment, comprising a discoid positioning body (5) with a medial hole and an anchoring body (7), provided for fixing the positioning body (5) to the bone through the medial hole (19).