[Object] To provide a ferrite sintered body and a ferrite core each of which has a high permeability, and a coil component produced by winding a metal wire around the ferrite core.
[Solution] A ferrite sintered body includes a crystal grain of a Ni-Zn ferrite and a grain boundary thereof, in which Ti is unevenly distributed in an outer region of the crystal grain, the outer region extending from an interface of the crystal grain to a length of 20% of a major axis of the crystal grain. The ferrite sintered body contains Fe, Zn, Ni, Cu, and Ti. When the total of components of Fe, Zn, Ni, and Cu in terms of oxides thereof is assumed to be 100% by mole, a composition of the ferrite sintered body is 48% by mole or more and 50% by mole or less of Fe in terms of Fe 2 O 3 , 29% by mole or more and 31% by mole or less of Zn in terms of ZnO, 14% by mole or more and 16% by mole or less of Ni in terms of NiO, and 5% by mole or more and 7% by mole or less of Cu in terms of CuO. The ferrite sintered body contains 0.05% by mass or more and 0.30% by mass or less of Ti in terms of TiO 2 relative to total 100% by mass of the components.