The present disclosure provides an iliac prosthesis, comprising: a prosthesis main body, the prosthesis main body including a first end portion contacted and matched with a sacrum and a second end portion contacted and matched with an acetabulum, a first screw hole being formed in the first end portion, a first screw seat being arranged in the first screw hole, the screw-rod structure including a connecting seat and a rod body, the connecting seat being connected with the prosthesis main body, and the rod body being fixed on the connecting seat； and an anti-dropping mechanism, the anti-dropping mechanism being arranged between the prosthesis main body and the connecting seat in a clamping manner. The technical solutions of the present disclosure can effectively, solve the problems of, unreliable supporting and easy fatigue break of the screw-rod system in the related technology.
