Abstract: The invention relates to a prosthesis for a leg amputee, comprising a thermoformed framework made of a thermoplastic material or of a laminated substance, covered with a coating material and comprising a socket (1), a leg part (2) and a prosthetic foot (3), one adjoining the other.According to the invention, the framework of the leg part (2) and the prosthetic foot (3) constitutes a monobloc assembly, produced in a single casting operation, and in that the prosthetic foot comprises, at the level of the sole, a cut having served for the extraction of the molding core and, at the level of the heel, above the sole, a cut (9) of wedge formation lending itself to a flexion of the rear of the sole relative to the leg part.