A series of M3Co16Ox (M = Cr, Ti, Zr, Fe, Mn) oxide catalysts wrapped by polymer nanofilm were developed by the solid-phase method, and the catalytic activities were investigated for low temperature oxidation of carbon monoxide under moisture-rich condition. The catalysts were characterized by HR-TEM, FT-IR, XRD, N-2 adsorption-desorption, H-2-TPR, CO-TPD and XPS techniques. The results reveal that the M3Co16Ox composite oxides are high-dispersive mesoporous materials coated by polymer nanofilm with an average thickness in the scope of 4-7 nm. The percentages of surface oxygen vacancy and lattice oxygen on the catalysts decrease in the following order: M3Co16Ox > Fe3Co16Ox > Zr3Co16Ox > Ti3Co16Ox > Cr3Co16Ox, which is consistent with their catalytic performances. Among all the prepared catalysts, the polymer nanofilm wrapped M3Co16Ox nanoparticles possess the highest Co3+/Co2+ ratio (1.56), the highest percentage of surface oxygen vacancy (17.5%) and lattice oxygen (62.2%), resulting in the best catalytic activity, such as, 100% conversion at 55 degrees C under moisture-rich condition (similar to 0.6 vol.%). Moreover, the M3Co16Ox catalyst also exhibits long-term catalytic stability ( > one month) even at a very high water vapor level (3.1 vol.%) and considerably low temperature (85 degrees C).