Dimethyl sulfide (DMS) and isoprene are important marine biogenic reactive gases that influence marine atmospheric chemistry and climate. Mesoscale and submesoscale oceanic processes may substantially regulate their marine emissions, yet the underlying mechanisms remain poorly understood. In 2024 and 2025, we investigated the spatial distributions and source–sink processes of DMS and isoprene within a typical anticyclonic eddy and a submesoscale front in the western North Pacific. The anticyclonic eddy significantly enhanced isoprene production and microbial consumption within the deep chlorophyll maximum layer, with rates approximately 2.5 and 2.0 times higher, respectively, in the eddy core than at the eddy edge. Isoprene accumulated in the subsurface layer and was transported into the mixed layer through vertical diffusion before being released into the atmosphere. DMS also accumulated in the subsurface eddy core and was transported laterally toward the eddy edge along isopycnal surfaces. The front uplifted the isoprene maximum layer from approximately 100 m to 50 m through isopycnal uplift and water-mass mixing, increasing its biological production rate by approximately 56%. The front also enhanced DMS cycling, with surface production rates, concentrations, and sea-to-air fluxes increasing by approximately 19%, 36%, and 52%, respectively, relative to the surrounding waters. These findings demonstrate that mesoscale and submesoscale oceanic processes exert substantial controls on the production, transport, and atmospheric release of marine biogenic reactive gases and should therefore be explicitly considered in assessments of oceanic trace-gas emissions.