The CeO_2@TiO_2 core-shell nanostructure catalyst prepared by a two-step hydrothermal method was used for selective catalytic reduction(SCR) of NOx with NH_3 in this study.The catalyst presented the obvious core-shell structure,and the shell was amorphous TiO_2which could protect the active center from the SO_2 erosion.The catalyst showed high activity and stability,excellent N_2 selectivity and superior SO_2 resistance and H_2O tolerance.Characterizations such as TEM,HR-TEM,XRD,BET,XPS,NH_3-TPD,and H_2-TPR were carried out.The results indicated that the catalyst had large surface area and the active sites were well dispersed on the surface.The NH_3-TPD,H_2-TPR and XPS results implied that its increased SCR activity might be due to the enhancement of NH_3 chemisorption and the increase of active oxygen species,both of which were conductive to NH_3 activation.The excellent catalytic performance suggests that it is a promising candidate for SCR catalyst. The CeO_2 @ TiO_2 core-shell nanostructure catalyst prepared by a two-step hydrothermal method was used for selective catalytic reduction (SCR) of NOx with NH_3 in this study. The catalyst presented the obvious core-shell structure, and the shell was amorphous TiO_2which could protect the active center from the SO_2 erosion.The catalyst showed high activity and stability, excellent N_2 selectivity and superior SO_2 resistance and H_2O tolerance. Characterizations such as TEM, HR-TEM, XRD, BET, XPS, NH_3-TPD, and H_2 -TPR were carried out. The results indicated that the catalyst had large surface area and the active sites were well dispersed on the surface. NH_3-TPD, H_2-TPR and XPS results implied that its increased SCR activity might be due to the enhancement of NH 3 chemisorption and the increase of active oxygen species, both of which were conductive to NH 3 activation. The excellent catalytic performance suggests that it is a promising candidate for SCR catalyst.