Offshore wind and wave energy potentials are commonly simulated by atmosphere and wave stand-alone models, in which the Atmosphere–Wave–Ocean (AWO) dynamical coupling processes are neglected. Based on four experiments (simulated by UU-CM, Uppsala University-Coupled model) with four different coupling configurations between atmosphere, waves, and ocean, we found that the simulations of the wind power density (WPD) and wave potential energy (WPE) are sensitive to the AWO interaction processes over the North and Baltic Seas; in particular, to the atmosphere–ocean coupling processes. Adding all coupling processes can change more than 25% of the WPE but only less than 5% of the WPD in four chosen coastal areas. The impact of the AWO coupling processes on the WPE and WPD changes significantly with the distance off the shoreline, and the influences vary with regions. From the simulations used in this study, we conclude that the AWO coupling processes should be considered in the simulation of WPE and WPD.