Wastewater treatment has stimulated researchers to develop highly efficient catalysts for the degradation of organic pollutants. The present work focuses on the design and investigation of a titanium dioxide (TiO₂)-based photocatalytic system with improved catalytic ability under visible light. TiO₂/reduced graphene oxide (TiO₂/rGO) and squaraine dye (SQ) sensitized TiO₂/rGO (TiO₂/rGO/SQ) composites were synthesized by a facile solvothermal method. The incorporation of SQ aims to enhance the photocatalytic efficiency of the synthesized composites and extend their activity by utilizing the visible-light spectrum. The composite materials were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), the Brunauer–Emmett–Teller (BET) surface area analysis, and UV–Vis diffuse reflectance spectroscopy (DRS). The synthesized composites were evaluated for the decolorization of the organic dyes Rhodamine B (RhB) and Fluorescein (FL) in aqueous solutions. The synthesized composites were evaluated for the decolorization of the organic dyes Rhodamine B (RhB) and fluorescein (FL) in aqueous solution. Under visible-light irradiation, TiO₂/rGO/SQ achieved 98% decolorization of FL and 86% decolorization of RhB within 180 min.