An ankle prosthesis (1) having a talar implant (2) designed to be implanted in or on the talus (3), a tibial implant (4) designed to be implanted in or on the tibia (5), and an intermediate implant (6) designed to be interposed between the tibial implant and the talar implant. The intermediate implant (6) is designed to be mounted to move relative to the talar implant (2) at a contact interface (7) in order to allow the ankle to move. The ankle prosthesis (1) has configurable coupling means (10) designed to enable the intermediate implant (6) to be arranged relative to the tibial implant (4) in a specific configuration chosen from among a plurality of possible configurations.