An infinitely expandable display apparatus and a driving method thereof are disclosed. An infinitely expandable display apparatus includes a cabinet including a plurality of display units each having an application specific integrated circuit (ASIC) embedded therein, a set board generating a driving command signal needed for driving of the cabinet, and a set interface circuit connecting the set board to the cabinet. The plurality of display units are connected to one another through a unidirectional interface circuit, and at least one of the plurality of display units transfers the driving command signal and an execution result signal based thereon to a neighbor display unit on the basis of a cascading scheme.