The utility model provides an artificial acetabular prosthesis, which relates to the technical field of artificial prostheses and comprises an acetabular cup, an extension portion, a lining and a femoral head prosthesis. The extension part is arranged on the edge of the acetabular cup; due to the arrangement of the extension part, the overall shape of the acetabular cup is set to be more than semispherical; a mounting belt is arranged on the outer surface of the lining; the section size of the mounting belt is smaller than the opening size of the extension part; the lining extends into the acetabular cup to be mounted; the mounting belt can only be mounted or separated from the opening of the extension part when being flush with the opening of the extension part; when the artificial hip joint prosthesis is in other positions, the lining cannot be disengaged from the acetabular cup, the technical problem that in the prior art, a lining in a traditional artificial hip joint prosthesis isprone to disengagement from the acetabular cup, and consequently joint dislocation is caused is solved, and the technical effect of reducing the risk that the lining is disengaged from the acetabularcup is achieved.