To solve the high-dam navigation issue of the world class Three Gorges Project (TGP) is one of the key technical issues of the TGP. Special requirements exist in the TGP double-lane five-step shiplock in terms of general layout of navigation structures, sedimentation hindering to navigation, hydraulics of the water-conveyance system, high and steep slope treatment, manufacture and technology of main metal structures and mechanical and electric equipment, which have been resolved step by step by scientific tests, verification and engineering practice.