The invention relates to a wing synchronous unfolding system of catapult unmanned aerial vehicle folding wings and a using method. The wing synchronous unfolding system comprises two wing extending units and a synchronous gear mechanism, and the wing extending units of left and right wings are enabled to rotate by 0-90 degrees around axis of a main gear through elastic resilience generated by compressing springs in the process of folding the wings to complete a folding and unfolding function of the wings; left and right cover plates are fixedly connected with a fuselage through retaining blocks with lugs; and by designing the synchronous gear mechanism, synchronous unfolding of the left and right wings is guaranteed. In order to reduce structural weight and improve flying efficiency, weight of each unit is reduced on the premise that structural strength is guaranteed. By the wing synchronous unfolding system, accurate positioning and reliable unfolding of the left and right wings of a folding wing unmanned aerial vehicle can be realized reliably, and catapult success rate of the unmanned aerial vehicle is increased, so that reliability of the whole unmanned aerial vehicle is improved substantially. The wing synchronous unfolding system has the advantages that the system is reasonable in design, easy to implement, low in cost and simple and quick in folding mode, and the wings after being folded are regular and attractive in appearance and convenient to carry.