A novel ceramsite coated with micro-cuprous oxide (Cu2O) catalyst was prepared and its photocatalytic activity was investigated by determining the degradation of methylene blue (MB) in aqueous solutions under Xe light. The results showed that the catalyst had many outstanding characteristics, such as higher BET specific surface area, larger pore size and stronger visible-light adsorption capacity, suggesting that it is a promising photocatalytic material. Under experimental conditions the initial concentration was 15 mg/L, pH was 3 and photocatalyst dosage was 0.5 g, and the degradation rate of MB reached 93.31% after Xe light was irradiated for 75min. The photocatalytic degradation of MB followed the pseudo-first-order kinetics model, with high correlation coefficient values (R2>0.95). Some major degradation intermediates and desired products were identified by GC-MS and IC, respectively. Finally, the degradation pathways of MB by the catalyst under Xe light were proposed.