To provide Mn-Zn ferrite reduced in the deterioration of DC superposition characteristics at a wide temperature range (-40°C-100°C).

The principal constituent composition of the Mn-Zn ferrite is constituted of 51.0-52.0 mol.% of Fe2O3, 18.5-22.0 mol.% of ZnO and the residue of MnO while minute amount of several arbitrary kinds among 0.5-1.5 mol.% of TiO2, SiO2, CaO, V2O5 and Nb2O5 is contained as auxiliary constituents while more than 2,100 of relative permeability can be obtained at the range of -40°C-100°C under a condition that the residual magnetic flux density thereof is lower than 50 mT and the magnetic bias at a normal temperature is 135 mT.