Disclosed is a magnetic core having improved reliability. The magnetic core includes 37 to 44 mol % of manganese (Mn), 9 to 16 mol % of zinc (Zn), 42 to 52 mol % of iron (Fe), a magnetic additive, and a non-magnetic additive, wherein the magnetic core has a permeability of 2,900 or more and a core loss of 500 mW/cm3 or less.