Catalysts of Sn/SiO2, Sn-Ni/SiO2, and Sn-Pd/SiO2 were prepared with the incipient wetness method. The Knight shift in the 119Sn NMR absorption peaks from these catalysts as well as a sample of powdered tin metal were monitored by the solid state NMR spectroscopy. The peaks from the tin powders and the tin on the Sn/SiO2 catalyst were anisotropic with the Knight shifts at 0.755% and 0.813%. The Knight shift of tin was changed on alloying the supported tin with nickel or palladium. These changes in the Knight shift suggested that the electronic properties of the tin atoms in the supported alloys were affected by the presence of nickel and palladium.