The one-pot photocatalytic synthesis of benzo[f]chromene was performed at room temperature by the addition of benzyl alcohol, malononitrile and β-naphthol in contact with an illuminated nano-SnO2/TiO2 composite. This study illustrated the potential of photochemical synthesis of benzo[f]chromene. A simple procedure was proposed for the synthesis of a nano-SnO2/TiO2 composite using the sol-gel method by hydrolysis of tin(iv) chloride and titanium(iv) chloride at room temperature in the presence of polyethylene glycol 200, diethanolamine, and distilled water. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and FT-IR were employed to characterize the proposed photocatalyst.