The deactivation of reforming catalyst in the DIR-MCFC was reported to be affected by dispersion, loading amounts, kind of support and so on. In this research, we checked the resistivities of catalysts prepared by the different methods, and examined the effect of liquid phase oxidation. The oxidized catalyst in a liquid phase showed the increased activity and dispersion even though the nickel species was supported by deposition-precipitation method. In order to investigate the role of the oxidation, TGA, TPR and XRD analyses were conducted. The increase in activity was ascribed to the strong metal-support interaction which was induced by liquid phase oxidation.