In terms of two kinds of hoisting systems of offshore drilling rig, winch hoisting and hydraulic cylinder lifting, the detailed comparative analysis is made in the installed power, drill string compensation system configuration scheme, weight center of gravity, center of mass, sampling operation, impact on hull, operational maintainability, etc., the advantages and disadvantages of two kinds of hoisting systems, winch hoisting and hydraulic cylinder lifting, adopting the different matching schemes are summed up, whose comparative analysis results can provide a reference for how to choose the hoisting system of offshore drilling rig.