The competition to dominate the nuclear energy decommissioning market is likely to get fierce with changes in nuclear energy policies worldwide. Advanced nuclear program countries have long expedited technology development of decommissioning nuclear power at the state level, so they have laid foundation for independent technology. By contrast, Korea has continued to keep running nuclear power by extending service life so it is not able to secure decommissioning technology now. We need to learn the advanced countries’ experience indirectly as we do not yet have the experience of decommissioning outdated nuclear power plants. To successfully decommission nuclear power plants in Korea that faces decommissioning of Kori unit 1 and enter the global decommissioning market, we have to secure core decommissioning technology that puts public safety first and foundation for industrialization.