Abstract: Organic pollutants of coking plant wastewater are very complicated，which are harmful to the environment and are difficult to be treated. Photocatalytic degradation of the organic pollutants in coking plant wastewater was investigated by using mixture of TiO2 and powder activated carbon (PAC) as photocatalyst. Synergistic effect can be obtained by combination of TiO2 and PAC. Better absorption can be obtained when TiO2 is doped with rare earth，and the mixed photocatalyst of Nd-doped TiO2 and PAC exhibited better photocatalytic degradation for the pollutants when the mass ratio of Nd-TiO2/PAC is 1. The effects of catalyst dosage，initial pH，initial COD concentration，aeration rate on treatment of coking wastewater by Nd-TiO2/PAC are investigated in this paper and the optimal process conditions are determined. The results show that the removal efficiency of COD can reach 89% under conditions：aeration rate 0.093 L/(Lžmin)，catalyst dosage 4.0 g/L，initial COD concentration 385 mg/L，pH=9.82，reaction time 90 min.