Acetabular prosthesis comprising: - an acetabular cup comprising an internal surface defining a coupling cavity, - an insert able to be inserted inside said coupling cavity and comprising an external surface, said acetabular cup and said insert having a common coupling axis and comprising respective clamping means (20, 33) for their reciprocal clamping in an assembled condition, wherein in a disassembled condition the coupling cavity of the acetabular cup has an internal diameter (Dc) which is less than the largest external diameter (Di) of said insert, wherein in the assembled condition the largest external diameter (Di') of said insert is equal to the largest internal diameter (Dc') of the coupling cavity of the acetabular cup, wherein the internal diameter (Dc, Dc') of the coupling cavity of the acetabular cup is considered in correspondence to a coupling plane between the acetabular cup and the insert defined along said coupling axis, wherein furthermore said clamping means comprise: - a first clamping surface made on said internal surface of said acetabular cup, - a second clamping surface made on said external surface of said insert, and cooperating with said first clamping surface, said first clamping surface and said second clamping surface having a truncated cone shape with an inclination (α, β) different from each other with respect to said coupling axis, so as to obtain a conical coupling between said insert and said acetabular cup, with variable interference (i), along said coupling axis, characterized in that said acetabular cup comprises a trabecular reticular structure, said trabecular reticular structure being a lattice of cells, achieving a plurality of three-dimensional cavities disposed, open and intercommunicating, connected with each other; wherein said acetabular cup is shaped so as to comprise a through aperture in correspondence to a polar region thereof, wherein said insert is shaped so as to comprise, in a polar region thereof, a centering element able to be inserted inside said through aperture. - an acetabular cup comprising an internal surface defining a coupling cavity, - an insert able to be inserted inside said coupling cavity and comprising an external surface, said acetabular cup and said insert having a common coupling axis and comprising respective clamping means (20, 33) for their reciprocal clamping in an assembled condition, wherein in a disassembled condition the coupling cavity of the acetabular cup has an internal diameter (Dc) which is less than the largest external diameter (Di) of said insert, wherein in the assembled condition the largest external diameter (Di') of said insert is equal to the largest internal diameter (Dc') of the coupling cavity of the acetabular cup, wherein the internal diameter (Dc, Dc') of the coupling cavity of the acetabular cup is considered in correspondence to a coupling plane between the acetabular cup and the insert defined along said coupling axis, wherein furthermore said clamping means comprise: - a first clamping surface made on said internal surface of said acetabular cup, - a second clamping surface made on said external surface of said insert, and cooperating with said first clamping surface,