To reduce machining and grinding costs and to provide the Ti alloy excellent in high temp. strength, particularly in high temp. fatigue strength, by incorporating specific amounts of S, Se, Te, and REM into a Ti-Al-V alloy of specific composition.

This alloy has a composition consisting of, by weight, one or more kinds among 0.001-0.3% each of S, Se, and Te, 0.005-1% REM, 2-7% Al, 1.5-5% V, and the balance Ti. Further, the inclusions in this alloy exist in the form of one or more kinds among, mainly, TiS, Ti-Se, Ti-Te, REM-S, REM-Se, and REM-Te compounds and double compounds consisting of these elements. Although it is necessary that S, Se, and Te are contained by the amounts not lower than their respective lower limits in order to form the inclusions and improve the machinability of the Ti alloy, hot workability is deteriorated when they exceed their upper limits. As to the content of REM, a content not lower than the lower limit is necessary to form the inclusions and also form the shape of the inclusions in the alloy into granular state and improve machinability, toughness and strength are deteriorated when if exceeds the upper limit.