TiO2 thin film was successfully synthesized by sol gel dip-coating teclmique on glass substrate. Fabricated film is characterized by Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM) and surface profile. The characterization results showed that the TiO2 crystal seed had nanosize, the TiO2 thin film was uniformly coated on the surface of glass substrate with 250 nm in thickness. The evaluation of photocatalytic efficiency of the thin film by degradation of methyl orange (azo dye) under UV light revealed that the presence of TiO2 photocatalyst enhanced the efficiency of dye decomposition. When the methyl orange concentration increased gradually (5 mg/l, 10 mg/l, 15 mg/l), the rate constants (k) of methyl orange degradation reaction decreased (0.0879, 0.0744, 0.0546).