According to the redox environmental property of cryptomelane, the phenol degradation in aqueous and acidified suspensions by native cryptomelane has been studied. The results are as follows: First, the degradation rate of 50 mL phenol solution whose concentration is 100 mg/L can almost be up to 100% when pH is 2.1, quantity of mineral is 10 mg/L, grain size of mineral is 160~200 mesh, temperature is 25℃, buffeting speed is 200r/min, and time is 8h. Second, illumination and oxygen don' t affect the degradation of phenol. Third, the reaction rate increases when pH decreases. Fourth, the reaction is most likely to take place when the grain size is relatively small while the quantity of mineral, temperature and buffeting speed are comparatively high. Besides, sodium chloride or calcium chloride doesn' t affect degradation of phenol, and degradation rate decreases when sodium phosphate or sodium acetate is added to the reaction solution. It has been deduced from the products that degradation of phenol is attributed to the oxidation of cryptomelane. This is an effective method to degrade phenol sewage. This study will extend the application range of cryptomelane.