Comparative investigations of the catalytic activity of molecular sieves of different types containing zirconium showed that Zr-pentasil, doped with cobalt oxide, had considerable oxidation activity with respect to nitrogen monoxide, but SCR activity of these samples is connected to the acidity of the surface, which is necessary to activate methane to reduce nitrogen monoxide. Mesoporous molecular sieves, doped with cobalt oxide, chromium and cerium oxides, did not appear to have catalytic activity with respect to selective reduction of nitrogen monoxide with methane or propane–butane mixtures. This is connected with the effect of structural factors and the absence of acidic B-centers.