In order to develop a perspective of the new metastable β titanium alloy——TB-13, the influence of ageing treatments on the microstructure and properties has been studied. The results show that TB-13 alloy displays high age strengthening effect and fine precipitation. During the one-step aging process, the higher the aging temperature, the coarser the α plate thickness. As a result, TB-13 alloy shows the lower the strength and the higher the ductility. The best combination of strength and ductility is acquired in the TB-13 alloy after solution treatment at 1133K following aging at 813K for 16h. The ultimate strength is near 1400MPa and the specific elongation is 7.0% by ageing. At last, the details of the transformation mechanism and microstructural evolution accompanying ω-assisted α nucleation during continuous heating are discussed.