The catalyst system: for tandem hydroformylation/hydrogenation of terminal alkenes to the corresponding homologated normal alcohol was developed The reaction mechanism for the Rh/Ru dual catalyst was investigated by real-time IR monitoring experiments and P-31 NMR spectroscopy, which proved the mutual orthogonality of Rh-catalyzed hidroformylation and Ru-catalyzed hydrogenation. Detailed investigation about Ru-catalyzed hydrogenation of undecanal under H-2/CO pressure clarified different kinetics from the hydrogenation under H-2 and gave a clue to design more active hydrogenation catalysts under H-2/CO atmosphere. The solely Ru-catalyzed normal selective hydroformylation/hydrogenation is also reported.