This study comprehensively explored the ecological roles, behaviors, and adaptive strategies of the enigmatic nocturnal hornet species Vespa binghami du Buysson, 1905 (Hymenoptera: Vespidae), in South Korea. Using time-series analysis, we identified the hornet's peak activity to be between 23:00 and 00:00, consistent with its dietary preference for species of the order Lepidoptera as identified through cytochrome c oxidase I metabarcoding. Metabarcoding revealed a specialized diet that predominantly consists of moths belonging to the family Noctuidae, suggesting a co-evolutionary predator-prey relationship. However, our sample size was limited; therefore, this observation should be considered preliminary. Our findings also provide evidence of opportunistic predation on bees, indicating adaptive flexibility in foraging behavior. Spatiotemporal analysis showed that the hornets exhibited peak activity during late summer and that they are mainly found at elevations between 100 m and 400 m. Despite their adaptability, sightings are regionally limited within South Korea. Observations indicated that the hornets prefer nesting in tree cavities, which have architectural features uniquely adapted to their nocturnal lifestyle. Taken together, these findings offer a multidimensional understanding of the nocturnal behaviors, specialized adaptations, and ecological significance of V. binghami. Moreover, they highlight the need for further multidisciplinary research to fully elucidate the role of this hornet in its ecosystem and its potential as a bioindicator of environmental stability and habitat quality.