The utility model relates to a marine hydraulic gangplank. The marine hydraulic gangplank comprises a plank body and a hydraulic oil cylinder; a running wheel is connected to the lower part of one end of the plank body, while a driving lug plate is connected to the other end of the plank body; the driving lug plate is hinged to a gangplank supporting lug plate which is fixed at a bank by use of a pin shaft; an oil cylinder support frame is fixedly connected to the driving lug plate; one end of the hydraulic oil cylinder is hinged to the oil cylinder support frame by use of a pin shaft, while the other end of the hydraulic oil cylinder is hinged to an oil cylinder supporting lug plate which is fixed at the bank by use of a pin shaft. A universal wheel is mounted at one end of the plank body; when the universal wheel is supported on a ship, and in case of luffing of the ship in the horizontal direction, the gangplank is adjusted in the supporting direction by turning the universal wheel so that the luffing of gangplank connection in the horizontal direction can be satisfied; the marine hydraulic gangplank is high in applicability.