The invention discloses a double-backboard structure, which comprises a backboard A and a backboard B, wherein a daughter board connector is embedded in the backboard A, a positioning pin seat is further fixedly installed on one side face of the backboard A, a mother board connector is embedded in the backboard B, a positioning pin is fixedly mounted on one side surface of the backboard B, the positioning pin is inserted into the positioning pin seat, the backboard B is connected with the backboard A through matching of the positioning pin and the positioning pin seat, the backboard B is parallel to the backboard A, the mother board connector is connected with the daughter board connector in an inserted mode, the mother board connector is electrically connected with the daughter board connector, the mother board connector and the daughter board connector can be detached independently or along with a back panel, the structure is firm, and maintenance is convenient. The invention furtherdiscloses an ATR case, which comprises a case bottom plate, a case panel, a case back plate, a case right plate, a case left plate, a case top plate, a case internal board, a backboard A and a backboard B, wherein rigid connection can guarantee stability of signals and a system.