The CdS/TiO2NTs nanocomposite was prepared through ion-exchange and precipitation reactions. The nanostructure properties of the composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance UV-visible absorption spectra (DRUVAS), fluorescence emission spectra (FES) and X-ray fluorescence analyzer (XRF). SEM results revealed that the lamellar sodium trititanate originating from the TiO2 particles individually curled to form the sodium trititanate nanotubes by self-assembled mechanism. The results of XRD, TEM and DRUVAS demonstrated that hexagonal phase CdS with about 8 nm particle size were homogeneously loaded on the surface of anatase TiO2NTs and the absorption edge of the composite was extended to the visible region. The CdS/TiO2NTs composite exhibited the highest activity of hydrogen production (1708 mL/g) by photocatalytic water decomposition in comparison with TiO2NTs and TiO2 powder under visible light irradiation (l > 400 nm) for 6 h