An adjustable mounting bracket, which is applied for mounting a display device, is provided by the present disclosure. The adjustable mounting bracket includes a wall panel, a plurality of extending rods, and a limiting structure. The plurality of extending rods are detachably coupled to the wall panel and configured to adjusted length of the mounting bracket. The limiting structure is arranged on the wall panel. A receiving space is formed by the limiting structure and the wall panel. The plurality of extending rods are engaged with the limiting structure and received in the receiving space. The limiting structure is configured to guide the plurality of extending rods to slide in the receiving space. The adjustable mounting bracket provided by the present disclosure can be easily assembled, meet the requirements of installation specifications and packaging specifications, and be suitable for promotion and application.