The invention discloses an agricultural unmanned plane used for spraying pesticide. The agricultural unmanned plane used for spraying pesticide comprises a plane body, and two wing devices arranged onthe two sides of the plane body respectively; each wing device comprises a guide rail support fixedly arranged on one side of the plane body, a guide rail is arranged on the guide rail support, a guide slide block is slidingly arranged on the guide rail, the external side of the guide slide block is connected with an accommodation support, the accommodation support is provided with a groove, a gear rack is arranged in the groove, and is capable of sliding relatively to the groove, the gear rack is arranged to be parallel to the guide rail, the accommodation support is connected with a first gear through a first rotating shaft, the accommodation support is connected with a second gear through a second rotating shaft, and the first gear and the second gear are arranged on the internal sideof the gear rack, and are designed to mesh the gear rack. When the agricultural unmanned plane is not used, the wing devices can be folded and stored in the corresponding guide rail supports, so thatoccupied space is reduced, and the wing devices are protected from being damaged. In flight, a undercarriage can be folded and stored in a cabin of the plane body, so that fight resistance is reduced.