Tin-promoted Ru/H-CMK-3 catalysts were prepared by a novel reductant-impregnation method for application in the hydrogenation of cinnamaldehyde. The catalysts were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) specific surface areas , X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The effects of the synthesis reaction conditions on the selective hydrogenation of cinnamaldehyde were examined in detail. The results showed that the mesoporous CMK-3 carbon material could disperse the catalytically active species better. Using appropriate amounts of Sn(IV) provided electron-rich Ru sites, which are one of the main catalytically active species. The interaction between Ru and Sn promoted the activation of C＝O in cinnamaldehyde. Furthermore, changes in other reaction conditions, such as temperature and pressure, greatly influenced the selective hydrogenation of cinnamaldehyde.