Abstract: A magnetic erasing head comprises a pair of magnetic core elements defining an erasing magnetic gap therebetween and facing to a travelling magnetic recording medium, a coil winding opening provided adjacent to the erasing magnetic gap on one of the magnetic core elements located on a trailing side relative to travelling of the magnetic recording medium and defining a depth of the erasing magnetic gap, and a coil wound through the coil winding opening to be provided an alternating current flow for generating erasing magnetic field at the erasing gap, the coil winding opening defining a core portion adjacent to the trailing side having a thickness substantially equal to the depth of the erasing magnetic gap.