To significantly improve the solar harvesting and electron transportation, Bi2S3/BiOI p-n heterojunctions were successfully formed on the surface of TiO2 nanotube arrays (TiO2 NTs/Bi2S3-BiOI) by a simple solvothermal method, and the morphology, composition and photoelectrochemical property of the TiO2 NTs/Bi2S3-BiOI were investigated by adjusting the concentration ratio of sulphur/iodonium. TiO2 NTs/Bi2S3-BiOI nanosheets and nanorods were prepared, and the self-assembled microflowers were also observed. The results indicated that flower-like TiO2 NTs/Bi2S3-BiOI showed high visible light absorption, photocurrent density and rapid photoelectrocatalytic removal of organic dyes and Cr(VI). The growth and photocatalytic mechanism were proposed to illuminate the high photoelectrochemical performances. The excellent photoelectrochemical activities drive the TiO2 NTs/Bi2S3/BiOI being superior environmental and energy materials in the applications of wastewater purification and solar cells.