Multiphase catalysis is used in many industrial processes; however, the reaction rate can be restricted by the low accessibility of gaseous reactants to the catalysts in water, especially for oxygen-dependent biocatalytic reactions. Despite the fact that solubility and diffusion rates of oxygen in many liquids (such as perfluorocarbon) are much higher than in water, multiphase reactions with a second liquid phase are still difficult to conduct, because the interaction efficiency between immiscible phases is extremely low. Herein, we report an efficient triphase biocatalytic system using oil core-silica shell oxygen nanocarriers. Such design offers the biocatalytic system an extremely large water-solid-oil triphase interfacial area and a short path required for oxygen diffusion. Moreover, the silica shell stabilizes the oil nanodroplets in water and prevents their aggregation. Using oxygen-dependent oxidase enzymatic reaction as an example, we demonstrate this efficient biocatalytic system for the oxidation of glucose, choline, lactate, and sucrose by substituting their corresponding oxidase counterparts. A rate enhancement by a factor of 10-30 is observed when the oxygen nanocarriers are introduced into reaction system. This strategy offers the opportunity to enhance the efficiency of other gaseous reactants involved in multiphase catalytic reactions.