Al2O3-TiO2 supported Pd-Ru bimetallic catalysts were prepared and characterized by X-ray photoelectron spectroscopy and X-ray diffraction (XRD) techniques. The catalytic system was evaluated in the partial hydrogenation of palm oil. Based on these results, it was deduced that core-shell model particles, with Ru cores, would be most likely formed in the bimetallic catalysts. As a result, the dispersing effect of ruthenium on palladium and the charge transfer from ruthenium to palladium may be closely related to the excellent catalytic performance. Besides, the highly dispersed TiO2 on gamma-alumina support seems to be crucial for inhibiting the formation of trans fatty acid.