The Cu/TiO2 catalysts modified by Sb were compounded through the sol-gel way and put into use for the selective catalytic reduction (SCR) of NOx with NH3. Experimental results suggested that CuSb/TiO2-0.4 exhibited the excellent NOx conversion and SO2 tolerance. Subsequently, the relationship between surface physicochemical properties and catalytic performance was also investigated by different characterization methods. From characterizations, the introduction of Sb for Cu/TiO2 could promote the generation of more Cu2+, surface adsorbed oxygen species and surface acid sites on CuSb/TiO2-0.4 catalyst. Furthermore, Sb species on CuSb/TiO2-0.4 could contribute to the formation of more surface ad-NOx and ad-NH3 species, which would enhance the NH3-SCR process effectively through both the Langmuir-Hinshelwood (L-H) and Eley-Rideal (E-R) mechanisms.