Treatment of a model detergent compound, linear alkylbenzene sulfonate (LAS), using photolytic processes was studied. In the photolytic degradation of LAS, both ultraviolet (UV) light at 254 nm wavelength and its combination with hydrogen peroxide (H2O2) were investigated. Based on first-order rate constants, it was shown that 5000 mg/L of H2O2 for degradation of a 100-mg/L solution of linear alkylbenzene sulfonate was optimum. Addition of H2O2 at different illumination times with UV light at 254 nm did not improve first-order rate constants compared with the addition of H2O2 at the start of illumination. Degradation rates of the model compound (LAS) with three detergents were compared.