Marine water sampling device

The invention provides a marine water sampling device, and relates to the field of marine sampling equipment. The device comprises a mounting plate, the top of the mounting plate is fixedly connectedwith two mounting brackets, a pay-off shaft is hinged between the two mounting brackets, the mounting plate is provided with a driving mechanism for driving the pay-off shaft, and the pay-off shaft isfixedly connected with a pay-off wheel; and a steel cable is fixedly connected to the pay-off wheel, and a base is fixedly connected to the end, away from the pay-off wheel, of the steel cable. According to the marine water sampling device, when sampling is needed, the mounting plate is firstly mounted on a ship or other tools, and then a hydraulic cylinder is started to adjust the position of asecond piston plate, so that the initial air pressure in an air pressure box is adjusted; and after the specified sampling position is reached, a driving motor is started to drive the pay-off shaft torotate, so a steel cable is