Abstract: Using illite as carrier and dicyandiamide (C₂H₄ N₄) as g-C₃N₄ precursor, a novel visible light responding g-C₃N₄/illite photocatalytic composite was prepared through chemical impregnation combined with thermal polymerization technique. The microstructure, interface and optical properties of the obtained photo-catalytic composites were characterized by XRD、FESEM、AFM、UV-Vis、BET and PL. In addition, using ciprofloxacin (CIP) as the target pollutant, the photo-catalytic activity of photo-catalytic composite was evaluated under visible light. The results indicate that the as-synthesized g-C₃N₄/illite sample exhibits significantly enhanced photocatalytic activity under visible-light irradiation, whose reaction constant rate is almost 11.26 times that of the pure g-C₃N₄. The g-C₃N₄ nanosheets are firmly attached on the surface of illite, which could effectively inhibit the recombination of photogenerated carriers and then further improve the adsorption capacity and photoactivity of g-C₃N₄ photocatalyst.