Hydrogenation of tetralin was done over a bimetallic Pd-Pt catalyst supported on amorphous Al2O3-B2O3 at a hydrogen pressure of 3.9 MPa at 553 K in the presence of dibenzothiophene (sulfur content of 500 ppm by weight). The resulting activity and selectivity were compared with those for Pd-Pt supported on amorphous SiO2-Al2O3, gamma-Al2O3, SiO2, and USY zeolites. Pd-Pt/Al2O3-B2O3 had high sulfur tolerance; it showed higher activity than Pd-Pt/SiO2-Al2O3, Pd-Pt/gamma-Al2O3, Pd-Pt/SiO2, or Pd-Pt/USY (SiO2/Al2O3 = 680), but slightly lower activity than Pd-Pt/USY (SiO2/Al2O3 = 40) Furthermore, Pd-Pt/Al2O3-B2O3 showed excellent hydrogenation selectivity. This catalytic system, therefore, is promising for practically reducing the aromatics in diesel fuels.