Abstract: An acetubular implant includes a cup for receiving an insert freely articulated in the cup, equipped with iliac expansions (8) and a plugging element; the cup consists of a hemispherical part extended by a cylindrical part whereto are attached the iliac expansions. The cylindrical part extends over substantially a half circumference of an equatorial edge of the hemispherical part and is defined by a plane (R) inclined on the equatorial plane. Part of the outer surface of the cup (2) is covered with a macrostructure (24) defining a set of raised parts with a series of equatorial and meridian grooves of predetermined shape such that the macrostructure is neither too rough nor too smooth.