A magnetic head for sliding on a recording medium for executing magnetic recording or magnetic reproducing of information includes a magnetic core having a recording/reproducing magnetic gap whose track width is defined narrow in accordance with high-ranking high track density, and an erasing magnetic gap which is disposed upstream of a medium-sliding direction, in such a manner that the erasing magnetic gap is adjacent to the recording/reproducing gap, and whose track width is defined wide in accordance with low-ranking low track density. A center of the recording/reproducing magnetic gap in a direction perpendicular to the track is shifted by a predetermined amount of shift in the direction perpendicular to the track with respect to a center of the erasing magnetic gap in the direction perpendicular to the track.