This study presents the results of hybrid energy storage system (HESS) and improved maximum power point tracking (MPPT) algorithm simulation analysis undertaken to improve the smoothing performance of solar photovoltaic (PV) plant installed in the ship power system. Frequency hierarchical control algorithm is used to assign high-frequency oscillation part to the supercapacitor and low-frequency oscillation part to the battery. Meanwhile, improved MPPT algorithm is also used to limit the maximum output power of PV plant, which can reduce the necessary installed capacity of HESS further. The effectiveness of the proposed method was verified under a typical ship power system model.