The invention relates to an automatic fruit screening and casing device, which is composed of a bottom plate, a movable arm, an adjustment arm, guide rails, a leading screw, a connecting frame, an air bag expansion hand, a control cabinet, a conveyor belt, infrared units, push rods, a fruit conveying tray, a stand, catching trays, and a photoelectric sensor. The movable arm is mounted over the bottom plate, the adjustment arm and the movable arm are connected together, the guide rails are fixed below the adjustment arm, and the leading screw is fixed in an end hole of the adjustment arm. One end of the connecting frame is sleeved on the two guide rails, and the other end is connected to the air bag expansion hand. The control cabinet is positioned behind the whole device. The conveyor belt is sleeved on the stand. The infrared units are fixed on the stand, and the detection part is over against the upper part of the conveyor belt. The push rods are below the infrared units. The fruit conveying tray is positioned at the stand end. The catching trays are fixed on the stand and are opposite to the push rods. The photoelectric sensor is fixed at one stand end close to the air bag expansion hand and is below the conveyor belt end. The device can separate damaged fruits, accurately screens fruits of different grades, and realizes quick casing.