SiO2-coated SnPt nanoparticle catalysts (SnPt@SiO2), comprised of core SnPt bimetallic nanoparticles covered with a porous SiO2 layer were prepared by a water-in-oil (w/o) microemulsion method. X-Ray diffraction studies of SnPt@SiO2 (Sn/Pt=1.0) indicated that the SnPt bimetallic nanoparticles consisted of a Sn-doped Pt phase and a Sn1Pt1 alloy phase. Transmission electron microscopy demonstrated that the SnPt bimetallic nanoparticles were covered with a thin silica layer. A higher selectivity of cinnamyl alcohol mediated by SnPt@SiO2 (Sn/Pt=1.0) catalysts was observed in comparison to Sn-Pt/SiO2 catalysts prepared by conventional co-impregnation methods. The synergy effect between the SnPt bimetallic core nanoparticles and the porous structure of the SiO2 layer increased the chemo-selective hydrogenation of cinnamaldehyde to cinnamyl alcohol.