Oxygen evolution is frequently the bottleneck determining the efficiency in the overall photocatalytic water splitting. Herein, for the first time overall water splitting reaction to H-2 and O-2 is realized on BiOCl/CuPc (copper phthalocyanine) composite from RhB (rhodamine B) solution under simulated solar light irradiation. The photosensitized RhB dye molecules supplied photo-generated holes which took part in the reaction of O-2 evolution. By loading CuPc, the efficiency of H-2 evolution is improved. On the base of the greatly enhanced photocurrent density, the considerable enhancement of performance can be attributed to the quick transfer of photogenerated electrons from the photosensitizer to the CB (conduction band) of BiOCl. Furthermore, as active electron traps, the oxygen vacancies on the surface of the BiOCl photocatalyst promote the separation efficiency of photo-generated electrons and holes, resulting in high photoactivity. This study presents a way that organic dye wastewater will be a useful system for the overall photocatalytic water splitting reaction to H-2 and O-2. (c) 2012 Elsevier B.V. All rights reserved.