The invention relates to a computer-controlled undercarriage type net overturning device which is formed by a hydraulic drive mechanism, a hydraulic linkage device, a vertical lifting arm, a horizontal extending arm, a center rotating rack, a servo motor and a pneumatic jaw, wherein the hydraulic drive mechanism, the hydraulic linkage device and the linkage sprocket chain of the hydraulic linkage device are arranged in the middle of the vertical extending arm; the center rotating rack is arranged at the front end of an adjustable front rocker arm; the adjustable rocker arm is connected to the vertical lifting arm; power of the center rotating rack is provided by the servo motor; the servo motor and a planetary reducer are arranged at one side of the adjustable front rocker arm; transmission is achieved by a driving sprocket chain; and the pneumatic jaw is arranged on the upper surface of the center rotating rack. According to the invention, net pieces are automatically stacked in a convex and concave manner according to the principle of vertical lifting of the hydraulic drive system, so that the net pieces are alternatively laminated with a normal one and an inverted one in sequence, and therefore, the net piece stacking thickness is greatly reduced, storage space is saved, hoisting, transportation and storage are facilitated, labor force is saved, and the device is safe and reliable and flexible in rotation.