An automatic sliding door has a rail, a reset component, a pulley set, and a door panel. The rail is mounted on a top surface of a door frame. The reset component is mounted on a first end of the rail and is fixed to the door frame. The pulley set is slidably mounted in the rail, and a bottom end of the pulley set extends out of the rail. The door panel is mounted at the bottom of the pulley set, and the pulley set drives the door panel to slide.