Pure La2O3 and La2O3-TiO2 mixed oxides are prepared by sol-gel method. Hydrodesulfurization catalysts containing 8 wt% MoO3 and 3 wt% NiO are prepared using these oxides and characterized by Brunauer, Emmett, and Teller (BET) surface area, pore volume, X-ray diffraction, differential thermal analysis, Fourier transform infrared and scanning electron microscopy. The effects of support composition have been investigated in order to determine their influence on hydrodesulfurization catalytic process. Hydrodesulfurization of thiophene model molecule reaction was carried out in a micro-catalytic reactor at 250C-425C and atmospheric pressure. Sulfided catalysts showed a wide range of activity variation as a function of support composition, which established that NiMo sulfided active phases strongly depend on the nature and composition of support. It is found that 10% La/Ti supported catalyst was the better catalyst for thiophene hydrodesulfurization. It was also tested at high pressure with a real feed Gas oil.