This paper deals with an automation system for steel construction based on a robotic crane. Employing an automation system for steel construction of high-rise buildings has following advantages: reducing risk factors in human operation, decreasing the construction cost, and shortening the construction period. The automated robotic crane system suggested in this paper consists of moving mechanism, robot manipulation system, and HMI (human machine interface). Moving mechanism is composed of boom, rail, and scissor-jack type manipulator. Using this mechanism, the robot manipulator can be located anywhere in CF (construction factory). The robot manipulation system is composed of a cabin and two robot arms. The cabin acts as a cockpit for the operator. The first robot arm has a bolting end-effector to assemble H-beams and the second robot arm has an alignment end-effector to align H-beams before assembling task. HMI system helps workers operate robot manipulators through a haptic device and a vision system. Also, it contains ITA (intelligent teaching agent) system that helps unskilled workers operate easily.