Abstract: Samples were prepared by glycine combustion at different calcination temperatures. Composition and apparent morphology of manganese oxide samples were studied by X-ray diffraction(XRD) and scanning electron microscope(SEM), respectively. By using resorcinol simulated degradation of wastewater, the catalytic property of manganese oxide was tested. The results demonstrate that the higher the calcination temperature, the better the manganese oxide crystallinity is. Moreover, we can get the standard manganese oxide crystal at about 550℃. The manganese oxide gets sintered when the calcination temperature is above 700℃. The catalytic degradation efficiency of manganese oxides prepared at different calcination temperatures to phenol class organic pollutant is in the order of 550℃> 325℃> 700℃. The degradation efficiency of phenol class organic pollutant by manganese oxide gets 20% raised, to 45%, under the same reacting condition, on the effect of H₂O₂.