Abstract: The invention relates to a printing cylinder that includes a support cylinder, at least one printing sleeve for mounting the support cylinder, and a recess provided on a lateral face of the sleeve and emerging from an interior wall, and at least one indexing device borne by the support cylinder and that can project from it, the recess and each indexing device cooperating in order to mount the sleeve on the support cylinder while registering its position. According to the invention, the printing sleeve has at least one ring in an extension of an interior wall and which projects from the lateral face. The ring protects the sleeve from impacts between it and the indexing device during mounting of the sleeve on the support cylinder.