A position detection apparatus includes a position detection target member, a magnet that moves in accordance with movement of the position detection target member, and a plurality of magnetic detectors provided on a surface opposite a movement plane of the magnet. A flat yoke is provided on the reverse face of the magnet. The magnetic polarity of a peripheral side part of the magnet is opposite to the magnetic polarity of a center part thereof. The peripheral side part is formed at a regional range that can be defined on the basis of a predetermined distance(s) measured from a side edge of the yoke.