Abstract: Abstract：Mesoporous -MnO2 and mesoporous -MnO2/montmorillonite composites (Mn-Mt) were prepared under laboratory by using KMnO4 and MnSO4 as raw material and the modified montmorillonite as the carrier, and the synthesized samples were characterized by XRD, SEM, BET techniques. Rhodamine B degradation tests were carried out with 100 mg/L Rhodamine B and 0.15g/L catalyst of -MnO2 or mesoporous -MnO2/montmorillonite. The degradation dynamics of Rhodamine B showed that Mn-Mt composite material has better catalytic properties to rhodamine B than -MnO2. After three recycles, -MnO2Mt did not exhibit any significant loss of catalytic activity, confirming the catalyst was essentially stable.