The invention discloses a folded launching and withdrawing device for an unmanned aerial vehicle. The folded launching and withdrawing device comprises a base, a folded beam, a launching frame, a launching air cylinder, a traction cable, winch rollers and a pulley set. The tail end of the folded beam is hinged to the base, and the launching air cylinder is fixedly arranged at the end of an inner cavity of the folded beam. The two winch rollers are arranged at the end of the folded beam. The two ends of the traction cable connected with the launching frame are connected with the two winch rollers respectively in a winding mode along a traction line formed by the pulley set. The folded launching and withdrawing device is easy to store and hide after being folded, and is convenient to carry and transport flexibly, a slide is long after unfolding, launching force is large, high controllability is achieved, launching and withdrawing are integrated, fast and continuous launching and withdrawing cross work can be carried out, the large launching type application range is achieved, the device adapts to all carrier-based and vehicle-mounted maneuvering modes, operating can be maintained through a low-power fuel engine or motor, and other guarantees are not needed.