A series of Pd/Na modified Al2O3 catalysts was prepared by deposition-precipitation method. These catalysts were characterized by X-ray diffraction, temperature programmed reduction, X-ray photoelectron spectroscopy, N-2 adsorption, CO pulse chemisorption and SEM-EDAX. The characterization data reveal the formation of a ternary oxide of Pd with Na for the catalysts at an optimum Pd to Na ratio. The activity of the catalysts studied for the room temperature hydrodechlorination of chlorobenzene, is also found to be maximum at this ratio.