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The electrochemical behavior of the V(IV)/V(V) couple in an aqueous solution of 2 mol dm(-3) H(2)SO(4)+2 mol dm(-3) VOSO(4) on a graphite electrode at different temperatures is studied by steady-state polarization and electrochemical impedance spectroscopy. The results show that the diffusion coefficient (D) of V(IV) species increases from 1.60x10(-5) to 3.15x10(-5) cm(2) s(-1) with temperature from 15 to 70 degrees C and the activation energy for diffusion of V(IV) species is 10.52 kJ mol(-1). The anodic oxidation of V(IV) is a mixed kinetic-diffusion controlled process at the anodic polarization ranged from 32 to 132 mV vs. open circuit potential (OCP). The rate constant of charge transfer for the anodic oxidation of V(IV) increases from 1.2x10(-5) to 17.7x10(-5) cm s(-1) with temperature varied from 20 to 60 degrees C, and its activation energy is 52.4 kJ mol(-1).