Previous studies show that the phase transition temperature of Ti6Al4V can be effectively reduced by electropulsing treatment, which may be related to the promotion effect of current on element diffusion. In order to verify the above conjecture, the diffusion experiments of the Ti6Al4V-pure titanium system under the action of electropulsing and heat treatment are carried out. The results show that the current can effectively improve the diffusion coefficients of aluminum and vanadium, and the promotion effect has no relationship with the direction of the current. Considering the inhomogeneity of the Joule heat distribution of the microscopic scale of the material, the hypothesis of “local hot spot” is proposed to explain the experimental phenomena. It is found that the hypothesis can make effective predictions of diffusion coefficients and explain the promotion effect of electropulsing on Ti6Al4V phase transition reasonably.