Palladium and cobalt bimetallic catalysts supported on sulfated zirconia (PdCo/SZ), obtained from different precursors of Pd (nitrate and acetylacetonate), were prepared to study their influence on the selective reduction of NO by CH 4 (SCR–CH 4 ). Catalysts with nominal Pd and Co concentrations of 0.2 and 2wt%, respectively were characterized by XRD, DRS, XPS and Raman microprobe spectroscopy. The Raman signals denote a superficial increase of the zirconia monoclinic phase during the preparation stage in the catalysts obtained from Pd(NO 3 ) 2 but structural alterations in the surface were not observed when the organic palladium salt was used. Co 2+ presence, very propitious for this reaction, was determined in fresh catalysts. Catalysts used in reaction exhibit the presence of Co 3 O 4 and PdO agglomerates on the surface, loss of sulfates and a total transformation of the tetragonal to monoclinic phase on the support surface. Influence on SCR–CH 4 of the Pd catalytic precursor was not detected.The catalyst from Pd(NO 3 ) 2 showed better stability than the catalyst from Pd(CH 3 COCHC(O)CH 3 ) 2 precursor.