A series of copper-doped Ti-Ce-O_x complex oxide catalysts were synthesized by sol-gel method and evaluated for selective catalytic reduction of NO by NH_3 at low temperature. The promotional effect of copper doping on their structure, acidity and catalytic activity were investigated by means of Brumauer-Emmett-Teller(BET), temperature-programmed reduction(H_2-TPR), X-ray diffraction(XRD), scanning electron microscopy(SEM), temperature programmed desorption(NH_3-TPD) and pyridine adsorption infrared spectrum(Py-IR) technologies. Results showed that the copper additives could improve the low temperature catalytic performance for selective catalytic reduction of Ti-Ce-O_x catalyst and the NO conversion efficiency of Ti-Cu-Ce-O_x catalyst reached above 90% at 150–250 oC(Ti/Cu=4). The introduction of copper could enhance the redox property of the Ti-Ce-O_x complex oxide catalyst, refine the particle size caused by lattice distortion and oxygen vacancy defect and enhance the acid amount of the Lewis acid site. Moreover, Ti-Cu-Ce-O_x complex oxide catalyst also had good anti-sulfur ability and anti-water influence, when injecting 300 ppm SO_2 and 10 vol.%H_2O, the NO conversion efficiency of Ti-Cu-Ce-O_x catalyst reached 80%. A series of copper-doped Ti-Ce-Ox complex oxide catalysts were synthesized by sol-gel method and evaluated for selective catalytic reduction of NO by NH_3 at low temperature. The promotional effect of copper doping on their structure, acidity and catalytic activity were investigated by means of Brumauer-Emmett-Teller (BET), temperature-programmed reduction (H 2 -TPR), X-ray diffraction (XRD), scanning electron microscopy (SEM), temperature programmed desorption (NH 3 -TPD) spectrum (Py-IR) technologies. Results showed that the copper additives could improve the low temperature catalytic performance for selective catalytic reduction of Ti-Ce-Ox catalyst and the NO conversion efficiency of Ti-Cu-Ce-Ox catalyst up to 90% at 150-250 oC (Ti / Cu = 4). The introduction of copper could enhance the redox property of the Ti-Ce-O x complex oxide catalyst, refine the particle size caused by lattice distortion and oxygen vacancy defect and enhance the acid amount o f the Lewis acid site. Moreover, Ti-Cu-Ce-Ox complex oxide catalyst also had good anti-sulfur ability and anti-water influence, when injecting 300 ppm SO_2 and 10 vol.% H_2O, the NO conversion efficiency of Ti- Cu-Ce-O_x catalyst reached 80%.