Method for sintering magnetic core

A method for easily sintering a magnetic core while preventing damage to the magnetic core caused by deformation or other problems, includes preparing a flattened tubular compact by forming the compact to have a flattened tubular shape and a through hole. A supporting plate made from a baked porcelain material or a metal material having a dimension that allows for insertion into the through hole of the flattened tubular compact, as well as a length that is sufficiently longer than that of the flattened tubular compact, is inserted through the through hole. The flattened tubular compact is placed inside of a sintering container having highly pure alumina powder spread therein so that the axial direction of the compact is horizontal. The flattened tubular compact is then sintered in a sintering furnace to produce the magnetic core.