Photolytic,photochemical,electrocatalytic and photoelectrochemical degradation of reactive red 3BS were studied comparatively using RuxPd1-xO2/Ti as anode and NaCl as the suppport electrolyte.The results showed that the photoelectrochemical discoloration efficiency could afford for more than 98% within 30 min.The synergic effect of photoelectrochemical process was apparently observed.Two controlled experiments performed on RuxPd1-xO2/Ti anode in NaCl solution showed that when the system was firstly treated electrocatalytically for 30 min followed by 30 min photochemical treatment,the electrocatalytically-treated intermediate presented obvious enhancement in photochemical activity,that is,after 2 min illumination,the discoloration efficiency increased from 21% to 96%.It was interesting to note that no such enhancement of discoloration effciency was observed when the system was firstly exposed to photochemical process followed by electrocatalytic process.