Knee joint prosthesis

The utility model relates to the technical field of medical instruments, and particularly discloses a knee joint prosthesis which comprises a bone marrow needle base body, a three-dimensional (3D) bone trabecula sleeve, a connecting seat, a guide plate, an extension connector and a joint face prosthesis which are sequentially arranged from top to bottom. The bone marrow needle base body, the 3D bone trabecula sleeve and the connecting base are the main body structure of the prosthesis and are coaxially arranged in an integrally formed mode, and a nail hole is formed in the bone marrow needle base body. The guide plate is arranged on the side face of the connecting base and provided with guide holes, and the guide holes correspond to the nail holes. The extension joint is respectively hinged with the connecting seat and the joint face prosthesis to simulate the activity function of a bone joint; the contour of the joint face prosthesis is the same as that of the bone joint end face. The fixing screw penetrates