The invention discloses a rapid and convenient labor-saving car frame overturning device. Through a clamping mechanism, a rotary mechanism and a limiting mechanism, a car frame is overturned through self-weight of the car frame, welding operation on the front face and the back face of the car frame is achieved, and the problems such as high investment and limited sites caused by motor drive or hydraulic drive car frame overturning are solved; and the device adopts the eccentric principle, the car frame is overturned through self-weight of the car frame, thus, the lightweight requirement of thestructure of the car frame overturning device is achieved, investment is greatly reduced, meanwhile, operability is ensured, the car frame is conveniently overturned with less effort, and the environmentally-friendly operation effect is achieved.