Abstract Analytic expressions for the temperature-dependent diffusion coefficient of oxygen along two directions in the α2-Ti3Al alloy are obtained using Landman's method. The estimation of oxygen diffusion coefficient as well as pre-exponential factor and the activation energy are performed using migration barriers calculated by the first principle method within density functional theory. The phonon frequencies required for estimating the jump rate are determined at initial and saddle oxygen sites. The factors that determine the oxygen diffusion in the alloy are revealed. The influence of impurities on the oxygen diffusion in the α2-Ti3Al alloy is discussed. The method applied in this work is validated by good agreement between the calculated diffusion coefficient of oxygen and available experimental data and theoretical results obtained within statistical approach.