The semi-submersible marine drilling platform is semi-submersible on the sea surface and can be applied to various marine environments of different depths. Propelled by the waves, it constantly swayed back and forth. The winch heave compensation control system is composed of a winch drum driven by an AC variable frequency motor, brakes, heave monitoring instruments, and a control center. When the platform heaves up and down, according to the motion signal feedback from the detection system, constant tension control is provided to achieve heave compensation. At this stage, the drawworks heave compensation control system has been applied to several (sets) semi-submersible offshore drilling platforms of Sinopec Offshore Drilling to ensure the stability of offshore drilling.