The invention discloses an adaptive supporting device for a composite wing wallboard. The adaptive supporting device comprises an installing support and further comprises an installing base, a first sliding way, a push block, a driving mechanism, a second sliding way and a movable supporting jaw. The installing base is fixed to the installing support. The first sliding way is arranged on the installing base, and the stretching direction of the first sliding way is vertical to a process open hole of the wing wallboard. The push block is installed on the first sliding way. The driving mechanism is installed on the installing base and used for driving the push block, and the end, away from the installing base, of the driving mechanism is of a wedge structure. The second sliding way is fixedly installed on the side, away from the installing base, of the first sliding way. The movable supporting jaw is installed on the second sliding way, and the bottom end of the movable supporting jaw is provided with a slope matched with the wedge structure. The process open hole of the wing wallboard is used for assisting in supporting the wing wallboard, and no additional part needs to be additionally arranged for the wing wallboard for being connected with supporting equipment; an adaptive supporting method is adopted, the purpose of small stress supporting is achieved, and it is avoided that the wing wallboard near a supporting point is damaged by stress concentration.