Four kinds of manganese oxides with either layered or tunnel structures were prepared by different methods. The structural features of the prepared materials were characterized by power X-ray diffraction, IR spectra and SEM observation. A compare analysis of IR spectra for these materials before and after the acid treatment was carried out. Band around 761cm −1 could be assigned to a characteristic adsorbent band of tunnel-type manganese oxides; while it was not observed in layer-type manganese oxides. After the acid treatment, the position and relative intensity of the bands in 300–1200cm −1 region showed an obvious change for layered manganese oxides in compare with tunnel-type manganese oxides. The variation of IR spectra could be used to distinguish layered manganese oxides from tunnel manganese oxides.