CORE OF FAST BREEDER REACTOR

PROBLEM TO BE SOLVED: To provide a core of a fast breeder reactor that can reduce time needed for reprocessing of a spent nuclear fuel material.SOLUTION: A core 1 of a fast breeder reactor includes an inner core fuel region 2 loaded with a plurality of inner core fuel assemblies, an outer core fuel region 3 surrounding the inner reactor fuel region 2 and loaded with a plurality of outer core fuel assemblies, and a radial blanket region 6 surrounding the outer core fuel region 3 and loaded with a plurality of blanket fuel assemblies. Each blanket fuel assembly includes transuranium elements, including plutonium and minor actinide, obtained by reprocessing a spent fuel substance of a spent fuel assembly of a fuel assembly including mixed oxide fuel, and a nuclear fuel substance including collected uranium.