A high-strength titanium alloy of the present invention includes Ti as a major component, 15 to 30 at % Va group element, and 1.5 to 7 at % oxygen (O) when the entirety is taken as 100 atomic % (at %), and its tensile strength is 1,000 MPa or more.Overturning the conventional concept, regardless of being high oxygen contents, it has been possible to achieve the compatibility between the high strength and high ductility on a higher level.