The installation manipulator of insulation box of Mark Ⅲ liquid cargo containment system on Liquefied Natural Gas (LNG) carrier is studied. The installation manipulator of insulation box on LNG carrier is developed, and the structure design, hydraulic system, control system, power supply system, and visual recognition system of the manipulator are discussed. The driving mode of the manipulator is composed of hydraulic driving, servo motor driving, and manual driving, which can ensure the high bearing capacity, flexibility, and installation precision.