The invention relates to a release system for a self-expanding endoprosthesis, comprising a catheter, an endoprosthesis (2) having a first volume-reduced shape under an external constraint and, after elimination of the external constraint, assuming a second expanded shape at the placement site and being movably arranged in the catheter, a means for holding (6, 7) the endoprosthesis (2) in the catheter as well as means suitable to exert the external force on the endoprosthesis (2), wherein the means for exerting the external force on the endoprosthesis (2) is a tubular film (3) whose distal end encloses the endoprosthesis (2) in its reduced-volume form and whose proximal end extends to the proximal end of the catheter in such a way that it can be withdrawn from the endoprosthesis (2) thus eliminating the external constraint. (Fig.1)
