The V2O5/TiO2(A) catalysts were prepared by the grafting and their Bronsted and Lewis acid sites were investigated with pyridine adsorption by using FTIR Spectroscopy. The results obtained showed that monolayer or less coverage of the surface of the support, TiO2(A), took place up to V2O5 content of 11.88%. When V2O5 amount was higher then 11.88%, the support was covered as multilayer. Pyridine adsorption studies showed that the number of the Lewis acid sites of the V2O5/TiO2(A) catalysts decreased with increasing of V2O5 amount. The number of the Bronsted acid sites increased with increasing V2O5 content, reached a maximum at 11.88 wt. % of V2O5 and then began to decrease with increased V2O5 content.