Mo-Co or Mo-Ni catalysts supported on alumina (Al2O3) have been widely used for hydrodesulfurization (HDS) of heavy petroleum fractions. In order to enhance the catalytic activities for HDS, a composite type support (TiO2-Al2O3) prepared by the chemical vapor deposition (CVD) method has been studied. We found that Mo catalyst supported on TiO2-Al2O3 showed much higher catalytic activity for HDS of dibenzothiophene derivatives than the catalysts supported on Al2O3.