The photocatalyst of g-C3N4/CdMoO4 nanosheets (CN-CMO) was prepared with different proportions.Its crystal structure,morphology,light absorption capability and chemical bond was characterized with SEM,TEM-EDS,XRD,FT-IR,DRS.The photocatalytic activities of sulfathiazole onto the materials under visible light were investigated.Results showed that the photo-degradation had the obvious characteristics of first-order kinetics.The rate constant for the photo-degradation of sulfathiazole by CN-CMO was at most 3 times or 10 times than that of g-C3N4 or CdMoO4,respectively.The increase of photocatalytic activity was due to the easier separation of the electron and hole in the CN-CMO.The photocatalytic activity of CN-CMO was affected by its concentration.The optimal dosage was 1.0 g/L.