Vanadia supported on sulfated Ti-pillared clays with different vanadia loading have been prepared and characterized. The catalytic activity of the synthesized materials in the selective catalytic reduction (SCR) of NO by NH3 in presence of oxygen have been evaluated. The results showed that the increase of vanadia content influences the reduction behavior of sulfate. It was found that the presence of small amount of sulfate (1%) with high vanadia content on the sulfated titanium pillared clay may affect a variety of catalyst properties, including the acidity and reducibility of catalyst, and the overall amount of sulfate species. The performance of vanadia supported sulfated Ti-pillared clay in the SCR reaction was compared to a physical mixture of pure V2O5 with sulfated Ti-pillared clay. From the results obtained, it appears that the presence of a Bronsted acid site in close proximity with the vanadia site on sulfated Ti-pillared clay results in a promoting effect on SCR-NO activity. (c) 2006 Published by Elsevier B.V.