The dependence of the amount of intermediates formed during photocatalytic degradation of five chlorinated organic compounds (trichloroethylene, tetrachloroethylene, trans-1,2-dichloroethylene, 1,2-dichlorethane, 1,1,2,2-tetrachloroethane) on the amount of hydrogen peroxide added of as an electron acceptor was investigated. The influence of the intermediates on the photodegradation rate was estimated.