The frame of the hydraulic bending machine is processed after welding to ensure high strength, high precision and high rigidity. The mechanical synchronization system is adopted, and the two sides of the slider are moved in parallel through the synchronization shaft. Equipped with upper mold deflection compensation device, and optional fast upper mold clamping device. The back gauge of the hydraulic press brake machine has high precision, and the adjustment includes electric quick adjustment and manual fine adjustment, and the operation is simple. The X-axis back gauge is driven by siemens motor, driven by a ball screw, guided by a linear guide rail, and the stroke of the Y-axis slider is controlled by siemens motor to ensure high positioning accuracy. The configured Estun E21 controller system can efficiently control the operation of X-axis and Y-axis to ensure high bending accuracy.