The JPDR (Japan Power Demonstration Reactor) is a power reactor which was first built in Japan. The life of a reactor is generally considered to be 30 to 40 years. So the decommissioning will be needed. Therefore, it is now necessary to develop decommissioning technologies, including dismantling techniques of these power plants. The concrete cutting robot with sawing and coring units by the remote control system has been developed for the highly activated biological shield dismantling. And this cutting system can remove cut concrete blocks from the biological shield wall. In the test, the cutting speed was controlled automatically and remotely. And this proves that the heavily reinforced concrete can be cut speedily, safely and continuously with precision. This system has been applied to the dismantling of the highly activated concrete of the JPDR.