A hull propulsion mechanism includes a ship body; a wind blade, which is set to the top of the ship body and has a plurality of sails for obtaining a rotating force from wind blade; a shaft, which sustains the wind blade and is a rolling axis as well for conveying the rotating force by the wind blade; a water pump, which is a power unit that circulates water by making use of a turning force from the shaft; and an engine, which obtains hull propulsion from screws that are rotated by a circulated water pressure from the water pump. With this configuration, the hull propulsion mechanism can obtain enough propulsive force without consuming fossil fuels.