Retractable luggage case

A retractable luggage case, comprising a case cover and a case bottom, wherein the case cover and the case bottom are connected by two X-shaped brackets, the X-shaped brackets are respectively located at a left side and a right side of the luggage case, the X-shaped brackets are foldable brackets, each X-shaped bracket is comprised of two support rods which are rotatably connected, a rotatably connected support rod connection point is located in a non-midpoint position of the support rods, an end of each support rod close to the support rod connection point is set as a rotating end, and the rotating end is rotatably connected to the case cover or the case bottom;

• and an end of the support rod far away from the support rod connection point is set as a sliding end, the sliding end is slidably connected to the case bottom or the case cover, a distance between the support rod connection point on the left X-shaped bracket and a rotatable connection point of the rotating end on the case bottom is equal to a distance between the support rod connection point on the right X-shaped bracket and a corresponding rotatable connection point of the rotating end on the case bottom, a synchronization rod is arranged between corresponding support rods rotatably connected to the case bottom, the synchronization rod is fixedly connected to the corresponding support rods, and the retractable luggage case is further provided with locking structures capable of locking sliding ends.