[en] In order to maintain continuous growth of nuclear power industry in Korea, several issues such as spent nuclear fuel management, safety of nuclear reactor and non-proliferation concerns, etc. should be kept in mind. Taking advantages of Korean nuclear reactor strategy of having both of the light water reactors (PWR) and heavy water reactors (CANDU) for electricity generation, DUPIC (Direct use of spent PWR fuel in CANDU reactors) nuclear fuel cycle concept has been suggested for one of the solutions of the PWR spent fuel management, while improving the utilization of uranium resources in proliferation resistant way. In addition, theoretical analysis of DUPIC fuel behaviors in the commercial CANDU reactors is under way to check the compatibility of DUPIC fuels in terms of reactor physics, safety and handling