Abstract: An acetabular prosthesis (1) includes a hollow hemispherical artificial acetabular cup (2) having expansion slots distributed over its periphery, and provided with teeth (11n,=1-3) on the outer surface, a threaded intermediate element (3) and a plastic insert (4). The intermediate element (3) is a hollow core with an outer hemispherical surface capable of being urged in contact against at least an internal meridian generatrix of each segment defined between the slots; the inside part close to the orifice of the acetabular cup (2) has a thread wherein is screwed the intermediate core (3); the internal diameter of the acetabular cup (2) orifice of the acetabular cup (2) in reception position before the intermediate element (3) is screwed, is smaller than the external diameter of the intermediate element (3).