Fugen Nuclear Power Plant, Advanced Thermal Reactor, was permanently shut down in March 2003 and it is at the decommissioning stage. Decommissioning Engineering Support System, DEXUS, has been developed to help planning of the optimal dismantling process and for carrying out the dismantling work safely and efficiently. Worksite Visualization System (WVS), as part of Dismantling Work Support System of DEXUS, has been developed to support the field workers to deal with the information on the dismantling facilities comprehensibly and intuitively. In this article, outline of the dismantling process of Fugen is first introduced, then a feasibility study on WVS is described.