TiN, TiC, TIC/TiN, and Mo electrodes for an Alkall Metal Thermo-Electric Converter (AMTEC) were prepared by ceramic processing and their cathodic polarization characteristics were studied at 600-800-degrees-C. The polarization characteristics for TiN and TiC electrodes were similar to those for the Mo electrode. Among three kinds of TiC electrodes with different morphologies, the electrode consisting of finer grains gave a higher power density (0.40 W cm-2) . The activation energies for the exchange current density were smaller for ceramic electrodes than for the Mo electrode. In the high current density region above about 1 A cm-2, a limiting current region appeared. When the vacuum level of the low temperature region, which was controlled by introduction of argon, was below 10 Pa, the power density did not depend on the vacuum level but, above 10 Pa, the power density decreased with increase of argon pressure.