The low solubility of gases in aqueous solution is the major kinetic limitation of reactions that involve gases. To address this challenge, we report a nanochannel reactor with joint gas-solid-liquid interfaces and controlled wettability. As a proof of concept, a porous anodic alumina (PAA) nanochannel membrane with different wettability is used for glucose oxidase (GOx) immobilization, which contacts with glucose aqueous solution on one side, while the other side gets in touch with the gas phase directly. Interestingly, it is observed that the O2 could participate in the enzymatic reaction directly from gas phase through the proposed nanochannels, and a hydrophobic interface is more favorable for the enzymatic reaction due to the rearrangement of GOx structure as well as the high gas adhesion. As a result, the catalytic efficiency of GOx in the proposed interface is increased up to 80-fold compared with that of the free state in traditional aqueous air-saturated electrolyte. This triphase interface with controlled wettability can be generally applied to immobilize enzymes or catalysts with gas substrates for high efficiency.