Atmosphere-ocean interactions are thermodynamically important in the development of explosive cyclones. An explosive cyclone which emerged in the Northwestern Atlantic in January 2018 received massive heat from the Gulf Stream and developed rapidly due to enhanced atmospheric instability. Ocean surface waves affect momentum and heat air-sea exchanges, but their roles in explosive cyclone development have not been examined. This study shows that waves enhance the development of the explosive cyclone using a coupled atmosphere-ocean-wave model. The developing waves increased sensible and latent heat supply by increasing the transfer coefficient and friction under the cyclone. The increased heat supply from the sea surface strengthened the convective instability in the lower atmosphere. The air was lifted to the middle troposphere near the bent-back front by a strong updraft and enhanced precipitation near the cyclone’s center. The resulting latent heat release produced positive potential vorticity in the lower troposphere and intensified the explosive cyclone development. Waves also enhanced vertical ocean mixing, and sea surface temperature (SST) warmed north of the Gulf Stream. Overall, the most dominant effect of waves for the explosive cyclone development was to increase the supply coefficients of sensible and latent heat. Introducing ocean surface waves into the numerical simulations improved the reproducibility of explosive cyclones, indicating the importance of waves in explosive cyclone development.