The purpose of the present invention is to provide a structure for linking an upper prosthetic leg part and a lower prosthetic leg part in a revolutionary prosthetic leg affording advantageous working effects not obtained in the prior art. A linking structure for an upper prosthetic leg part 1 fitted to the body, and a lower prosthetic leg part 2 linked to this upper prosthetic leg part 1 to constitute a prosthetic leg F, a ground-contacting part 2a being provided at a lower end wherein the structure is constituted by a linking part 3 provided to either the lower prosthetic leg part 2 or the upper prosthetic leg part 1, and a mated linking part 4 provided to the other and adapted to mate with the linking part 3 and having retaining elements 6, 7 which protrude into the mating aperture 4a of the mated linking part 4 and retain the linking part 3 positioned within the mating aperture 4a.
