A full-automatic double-grey-paperboard stacking device comprises limiting frames on the two sides. The distance between the two limiting frames is larger than the width of double grey paperboards. Avertically-arranged crawler device is mounted on the outer side face of each limiting frame. A rotating shaft of each crawler device is in linkage with a motor and is provided with a conveying bar. Bearing devices are mounted on the conveying bars at fixed intervals, and each bearing device comprises a bearing plate and a fixing block connected with the bearing plate. The fixing blocks are fixed on the conveying bars, the bearing plates penetrate out of the conveying bars and extend out of the inner side faces of the limiting frames. The fixing blocks are provided with pneumatic devices, and the pneumatic devices control the bearing plates to extend out of the inner side faces of the limiting frames or retract into the inner side faces of the limiting frames. Infrared detectors are arranged at the positions, below the bearing plates, of the fixing blocks, and detect the double grey paperboards on the inner sides of the limiting frames. The crawler devices, the pneumatic devices and theinfrared detectors are electrically connected with a control device. The full-automatic double-grey-paperboard stacking device achieves the full-automatic stacking and collecting operation of the double grey paperboards, and greatly improves the production efficiency.