Photocatalytic methods with TiO2 catalyst were successfully applied to the decomposition of many organic contaminants. In this paper the performance of an electrochemical-assisted photocatalytic degradation of textile washwater containing procion blue dye was investigated. Several operational parameters to achieve optimum efficiency of this electrochemical-assisted photocatalytic degradation system have been done. The main objective was to determine the chemical oxygen demand (COD) and colour removal of the organic pollutant. The effects of pH, current density, supporting electrolyte, the irradiation time and photocatalyst on treatment efficiency were studied. The results showed that electrochemical-assisted photocatalytic process was used efficiently with 90% COD removal and complete colour removal after 7 h treatment. (c) 2007 Elsevier B.V. All rights reserved.