In this work, we report the synthesis of TiO2 nanoparticles coupled with a metal sulfide semiconductor having narrower band gap i.e. Bi2S3, so as to utilize the maximum fraction of sunlight and to improve the photocatalytic performance of TiO2. Bi2S3 nanotubes-TiO2 nanoparticle heterostructures were successfully synthesized using a facile solvothermal process. The composition, morphology, optical and pore structural properties of the as prepared photocatalyst were studied by various techniques such as powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), fourier transformation infra-red spectroscopy (FTIR), photoluminescence spectroscopy (PL) and Brunauer-Emmett-Teller (BET) surface area analysis. It was observed that the synthesized heterostructures were composed of high density of TiO2 nanoparticles along with Bi2S3 nanotubes. The hetero-nanostructures composed of crystalline anatase TiO2 and orthorhombic Bi2S3 were synthesized, with high visible light response and surface area. The synthesized heterostructured photocatalyst was further explored for the degradation of a toxic azo dye i.e. amaranth dye under solar light and it exhibited superior photocatalytic activity as compared to bare Bi2S3 and TiO2.