Hydrodesulfurization of dibenzothiophene (HDS of DBT) has been carried out over CoMo/Al(2)O(3)-TiO(2) catalystsin a batch reactor at 320 degrees C and 5.5MPa. The supports were prepared with different raw materials and nitrilotriacetic acid (NTA) was used as a chelator at different concentrations. X-ray diffraction, Fourier transform infrared spectroscopy, temperature programmed desorption of NH(3), and Brunauer-Emmett-Teller surface area experiments were used to characterize the catalyst samples. The results showed that the oxide prepared by an impregnation method with gamma-alumina and tetraisopropyltitanate as the raw materials was the best support, having the highest surface area (239m(2) . g(-1)) and the highest acidity (1.112 mmol(NH3) . g(-1)), and the catalyst with an NTA/Co mole ratio of 0.6 was the best sample, having a hydrodesulfurization activity value (on a pseudo first order kinetic constant basis) similar to 1.5 times higher than that of a CoMo/Al(2)O(3) catalyst.