The present invention discloses a composition of a knee implant comprising biomaterials such as combination of Ti—Nb—Zr alloy and tantalum to support osseointegration. The present invention further discloses a method of manufacturing customized patient-specific knee implant using 3D printing technology to suit the patient. The method involves the use of high energy source such as fiber laser or electron-beam. The base plate is mounted on the CNC. The energy source creates a melt pool on the base plate and the energy source is fed with a biomaterial in the form of wire or powder. The biomaterial is deposited on the base plate layer by layer, which solidifies in the melt pool of the base plate. The knee implant thus fabricated suits the elastic modulus of the bone and is useful as customized implant in patient undergoing replacement surgery.