The invention relates to a quickly assembled and disassembled combined chair which comprises a backrest, a chair seat top plate, a chair seat base plate, vertical columns, a folding hinge, fixing buttons and lock buckles, wherein the backrest is arranged on one side of the top of the chair seat top plate; the backrest is integrally connected with the chair seat top plate; the vertical columns are respectively arranged at four corners of the bottom of the chair seat base plate and are fixed through the lock buckles; the chair seat top plate and the chair seat base plate are connected through the folding hinge; the fixing buttons are arranged on the side walls of the chair seat top plate and the chair seat base plate on the backrest side; the chair seat top plate is rotated for 180 degrees around the folding hinge; and the chair seat top plate is folded and then is buckled on the chair seat base plate and is fixed by the fixing buttons. The chair designed according to the invention is high in practicability, is conveniently detached and assembled and is conveniently transported and carried.