The invention discloses a welding device for machining of a general aviation unmanned aerial vehicle. The welding device comprises a tank body, supporting legs are fixedly connected to the two sides of the bottom of the tank body, antiskid pads are fixedly connected to the bottoms of the supporting legs, fixing plates are fixedly connected to the two sides of the top of the tank body, and a top plate is fixedly connected to the tops of the fixing plates. Through cooperation of a first sliding groove, a second sliding groove, an electric telescopic rod, a movable block, a first sliding block, apull rod, a fixed block, a movable plate, a second sliding block, a telescopic column, a spring, a movable plate, a clamping plate, a buffer cushion and a controller, the advantage of good clamping effect is achieved, the problem that due to poor clamping effect of an existing welding device for machining of the general aviation unmanned aerial vehicle, workpieces of the unmanned aerial vehicle are damaged during welding is solved, the general aviation unmanned aerial vehicle does not slide in the welding process, the welding position accuracy is improved, and the number of defective workpieces of the unmanned aerial vehicle is reduced.