[en] A three-dimensional graphic simulation has been carried out for the dismantling process of the Rotary Specimen Rack(RSR) in the Korea Research Reactor-1 and 2 (KRR-1 and 2). First of all, the general steps of the graphic simulation were established and reviewed for the dismantling process of the object. Four dismantling processes, which are the removal of RSR, reactor core region, beam tube, and thermal column and activated concrete, were selected for the graphic simulation on the virtual space by the consideration of the activation, worker training, work difficulty and so on. In the present study, the dismantling procedure of the RSR was divided into several steps and its visual simulation was performed by the 3D graphic software. Finally, the simulation result was converted to moving file with extension of AVI so that easy approach can be made on window OS system