This paper describes the development of a mobile robot capable of clearing such obstacles as counter weights, anchor clamps and torsion tower. The mobile robot walks on overhead ground wires on power tower. Its ultimate purpose is to automate to inspect the defect of power transmission line. We are trailing the use of transmission line inspection robot to help detect damage to transmission line conductors and associate fittings. The remotely piloted aerial vehicle would provide a high level of analysis and clear view of damage. Its ultimate purpose is to inspect the defect of transmission line. The robot consists of 6 motors, 4 wheels and arm. Visible light camera is also used to obtain video information. A prototype robot was developed with careful consideration of mobility. Results experiments demonstrate that the robot can be applied to execute the navigation and inspection tasks.