A plate overturning device is specifically composed of a first frame, a second frame, a motor frame, a motor, a servo motor, a roller, a plate overturning frame, a rotating shaft, a bearing set, a chain and a belt. All the components of the device are simple in structure. In the implementation process, all the components are cooperative with one another and act in harmony. In the application process, a compound plate is placed on the plate overturning frame, then, the motor and the servo motor are started at the same time, and the rotating shaft drives the roller to rotate under driving of the two motors. The plate overturning frame arranged on the roller drives the compound plate to be overturned forwards. Then, the compound plate is placed in a next set of plate overturning frame, and therefore continuous forward overturning is carried out. When the plate overturning device is used, the automation degree is high, the plate overturning process is convenient and fast, and efficiency is high. Meanwhile, the plate overturning device is simple in structure, easy to manufacture, low in price and worthy of being greatly popularized.