A distance sensor and a washing machine including the distance sensor are provided. The washing machine may include a main body having a laundry loading hole formed therein, a door coupled to the main body, at a position corresponding to the laundry loading hole, and a plurality of reed sensors. The door may include a magnet disposed therein. The plurality of reed sensors provided in the main body and react to the magnet provided in the door to determine an open/closed state of the door.