The invention provides a marine wind power boosting device which comprises a rotating drum, a blade fan, a rotating drum driving motor, a dynamics strengthening disc, a rotating drum rotating shaft, blade rotating motors and horizontal rotating shafts, wherein the rotating drum driving motor is mounted at the bottom of the rotating drum and is connected with the rotating drum through the rotating drum rotating shaft; the blade fan consists of a group of blades; the blades are symmetrically arranged around the rotating drum. The marine wind power boosting device is characterized in that the section plane of each blade of the blade fan is an arc; the angle range of the central angle corresponding to each arc is 0.5-3 radians; the horizontal rotating shafts are arranged at the roots of the blades; the blade rotating motors are mounted on the horizontal rotating shafts; and the dynamics strengthening disc is mounted at the top end of the rotating drum, and is coaxially, concentrically and fixedly connected with the rotating drum. According to the marine wind power boosting device, the rotation effect is additionally adopted on the basis of a Flettner rotating drum, so that wind energy is used more fully, the rotating drum can realize the self-starting effect, the rotating speed of the rotating drum relative to wind speed is increased, the boosting effect of the rotating drum is improved, and the energy consumption is reduced.