Abstract: A modular reverse shoulder prosthesis, comprising: a stem (110) comprising a tapered body (111) and a first annular housing (112); a tray (120) comprising a dome element (121) for insertion into the first annular housing (112), and further comprising a second annular housing (122); a liner (130) comprising an engaging element (131) for at least partial insertion into the dome element (121), and further comprising a joint concave element (132) configured for coupling with the second annular housing (122). The second annular housing (122) of the tray (120) comprises a raised edge (123) configured to support the joint concave element (132) and which defines an overall outline having a different development in height at least in diametrically opposite portions (123a; 123b) of the tray (120).