Herein, polyaniline-tin oxide (PANI-SnO2) nanostructured materials (NSMs) were prepared by incorporating SnO2 nanoparticles into the polyaniline (PANI) chain produced from aniline monomers. The structural, morphological, and optical features of materials were described using the scanning electron microscope (SEM), Fourier-transform infrared (FT-IR), powder X-ray diffraction (pXRD), and ultraviolet-visible (UV–Vis) spectroscopy. While a thermogravimetric analysis (TGA) was performed to assess the thermal stability of NSMs. Additionally, the as-prepared PANI-SnO2 NSMs were employed as photocatalysts to degrade several dyes, including rhodamine B (RhB), methyl orange (MO), methylene blue (MB), and methylene red (MR). The PANI-SnO2 photocatalyst showed degradation efficiencies of 84 %, 90 %, 92 %, and 60 % for RhB, MR, MO, and MB, respectively. Various factors, such as the amount of catalyst used, the amount of dye present, the effect of pH, and temperature, were also examined to determine the ideal conditions for degradation. The results showed that the photodegradation efficiency (PDE) of dyes was affected by these factors. Finally, the kinetics studies revealed that the PANI-SnO2 NSMs follow the pseudo-first-order kinetics, which makes them ideal for large-scale degradation of biological and chemical contaminants.