Offshore photovoltaic and marine current energy belong to marine clean energy. Utilization of marine clean energy plays important roles in improving the ecological environment and mitigating climate change. This paper introduces a hybrid marine energy system of marine clean energy. The virtual value and reference value of DC voltage determine whether the battery charges or discharges. When the SOC (State of Charge) of the battery exceeds 80%, the energy storage system stops working and the renewable energy generation system outputs power for hydrogen production. A simulation model of a marine clean energy hybrid power generation system was created and simulated in MATLAB/Simulink. The simulation results show that the system can operate steadily with the proposed charge-discharge management strategy.