The invention discloses a supporting device for welding circuit boards. The supporting device comprises a base plate and a backing plate fixedly connected with one end of the base plate, wherein a pair of supporting plates are arranged on the base plate in parallel; support plates are arranged below the opposite sides of the two supporting plates; a hydraulic cylinder lifting mechanism is arrangedat the back of the two supporting plates respectively; each hydraulic lifting mechanism comprises a hydraulic cylinder, a connecting plate and a pressing plate; the hydraulic cylinders are fixed on the base plate; a piston head of each hydraulic cylinder is connected with the corresponding connecting plate; each connecting plate is provided with the corresponding pressing plate matched with the corresponding support plate; rubber cushions are arranged on the pressing plates and the support plates respectively; and a control switch for controlling the lifting of the hydraulic cylinders is arranged on the base plate. The supporting device is simple in structure and convenient in operation, and protection measures for edge fixed parts of the circuit boards are added.