An α+β type titanium alloy wire contains, in mass %, Al: 4.50 to 6.75%, Si: 0 to 0.50%, C: 0.080% or less, N: 0.050% or less, H: 0.016% or less, O: 0.25% or less, Mo: 0 to 5.5%, V: 0 to 4.50%, Nb: 0 to 3.0%, Fe: 0 to 2.10%, Cr: 0 to less than 0.25%, Ni: 0 to less than 0.15%, Mn: 0 to less than 0.25%, and the balance being Ti and impurities, the contents of Al, Mo, V, Nb, Fe, Cr, Ni, and Mn satisfying an equation, in which an average aspect ratio of an α crystal grain is 1.0 to 3.0, a maximum crystal grain diameter of the α crystal grain is 30.0 μm or less, an average crystal grain diameter of the α crystal grain is 1.0 to 15.0 μm.