A V-4Cr-4Ti alloy and pure V were oxidized in flowing argon for 0.5-8h and subsequently annealed in vacuum for 16h at 973K. The oxygen of 1000-9000ppm was introduced into the V-alloys with little nitrogen, where oxygen was concentrated in region near the surface. By the annealing, oxygen was homogeneously diffused into depth of 150µm. The diffusion depth of oxygen in V-4Cr-4Ti is much smaller than that of pure V, because of Ti-O precipitates formed as oxygen trap. The study indicated that it is feasible to control oxygen level and distribute in the surface region of the vanadium alloys.