The effect of the deformation amount on the microstructures and mechanical properties of the WSTi544221 titanium alloy as-rolled bars was investigated. The Φ10 mm bar was treated at different solution and aging treatments,and the tensile properties and microstructures were studied. The results show that the grain sizes of the bars are refined,and the strength increases as the deformation amount increasing. The ductility keeps in original level. When the alloy is treated by 870 ℃ × 1 h/WC + 520 ℃ × 6 h/AC treatment,an improved strength and ductility can be achieved with the tensile strength at 1 610 MPa,yield strength at 1 531 MPa,elongation at 12%,and reduction of area at 43%.