The polarisation behaviour of Ni/3 mol % Y2O3-ZrO2 (Ni/Y-TZP) cermet electrodes for H-2 oxidation reaction has been investigated by the galvanostatic current interruption (GCI) over a wide range of H2O content and temperature in both undiluted and diluted H-2 fuel. The electrode performance increases with H2O content with a maximum at 14% H2O. The reaction orders with respect to partial pressure of H2O and H-2 are 0.5 and 0.1, respectively. The activation energy for the reaction is about 70 kJ mol(-1) in the H2O content range between 4 to 14% in undiluted H-2 and in the H-2 content range between 14 to 96% in diluted H-2. The polarisation behaviour was analysed by fitting the measured data with the Nernst-type concentration equation and an empirical rate equation. The results have demonstrated that charge transfer process may play an very important role in the polarisation behaviour for H-2 oxidation reaction on Ni/Y-TZP cermet electrodes. The deviation of the calculated data according to the empirical rate equation from the measured polarisation data at high current densities and low H-2 contents indicates that the reaction is limited by at least two electrode processes.