Vapor phase benzyl alcohol (BnOH) oxidation reaction is investigated over a pre–synthesised morphologically designed shape controlled spherical silver nanoparticles (AgNPs) decorated on manganese oxide nanorods (α–MnO2NRs) in the presence of air. The combination of silver nanoparticles and the α–MnO2NRs interface enabled the increased oxygen vacancies (Ov) and exhibited the strong metal–support interactions (SMSI) in surface oxygen activation. The effect of Ag loadings is significant and the optimal 1 wt% Ag loaded catalyst (1Ag/MnO2NRs) showed excellent performance in benzyl alcohol oxidation due to high adsorption capacity, enhanced oxygen vacancies and red–ox properties. The DFT calculations confirmed that the high BnOH surface adsorption was exhibited over Ag modified MnO2NRs than the bare α–MnO2NRs. The optimized 1Ag/α–MnO2NRs catalytic system achieved 2.6 fold higher activity compared to bare α–MnO2NRs. These results provided novel insights on the rational design of shape dependent metal/metal oxide based heterogeneous catalysts.