The invention discloses a rolling-relieving system based on a moving slide block. The rolling-relieving system comprises a power part, a track frame part, the moving slide block and a control part; the control part is used for coordinating work of the whole system; the power part provides power for moving of the moving slide block in the track frame part; when the ship rolling angle is greater than a certain numerical value, the control part starts a servo motor, the servo motor drives the moving slide block to conduct reciprocating movement in the frame according to a certain period, ship sway damping is increased, and thus ship rolling is eliminated or relieved; and when the ship rolling angel is decreased to a certain numerical value, the servo motor is stopped, and the system stops working. The rolling-relieving system has the advantages of simple structure, small size, large rolling-relieving torque, rapid response and the like, and ship rolling can be effectively relieved or eliminated.