The mechanical bio-functionalities such as tensile properties, Young's modulus, and fatigue strength of low-modulus β-type Ti-29Nb-13Ta-4.6Zr (TNTZ) with the addition of different amounts of TiB2 or Y 2O3 have been studied. The added TiB2 is precipitated as TiB, whereas the Y2O3 appears as Y2O3 in TNZT. The microstructures are refined by the TiB and Y2O 3precipitates. Young's modulus of TNTZ with TiB and Y 2O3 precipitates remain low, and are almost similar to Young's modulus of TNTZ without TiB and Y2O3 precipitates. TNTZ with the addition of 0.1 and 0.2 mass% B, and 0.2 and 0.5 mass% Y show a good balance of the strength (tensile strength) and ductility (elongation). The fatigue strength of TNTZ can be improved by adding a small amount of TiB 2 and Y2O3 while the Young's modulus remains low.