Recently there is increasing demand for the development of new -type titanium with a low elastic modulus for surgical orthopaedic implant applications. In this paper, we developed a new Ti-Mo-Zr alloy based on the d-electron alloy design theory. The designed Ti-12Mo-5Zr (at%) alloy was then produced using ingot metallurgy and evaluated pertaining to the effect of heat treatment on the microstructure and mechanical properties. The alloy exhibited a relatively low Young’s modulus similar to some typical orthopaedic titanium alloys. Yield strength, tensile strength and Young’s modulus of the alloy decreased after solid solution treatment. The mechanism by which heat treatment affects the mechanical properties is discussed.