The invention provides a modified multifunctional drainage device for thoracic surgery. The modified multifunctional drainage device for the thoracic surgery comprises a push rod, a mobile seat, a moving wheel with brake pads, a push handle, a hook, a mounting base, a rotary receiving protective wheel structure of a drainage tube, a storage tube, a connector, a plastic bottle cap, a drainage bottle, a drainage flexible catheter, quick disassembly docking drainage head, a liftable adjustable fixed rail structure and an observable fast fixed barrel structure, wherein a bolt on the lower longitudinal side of the push rod is mounted on the left end of the mobile seat. The modified multifunctional drainage device for the thoracic surgery has the advantages that with the arrangement of a fixed barrel body, a fixed seat, a fixed suction cup with screws, a crocodile clip and a connecting block, adsorption and fixing functions of the fixed barrel body are increased, fixing work of the drainagebottle is guaranteed, and operational intensity is reduced; with the arrangement of a drainage plug, a connecting pipe, a fastening nut, a check valve, a lock nut, a docking pipe and a connecting pipehead, real-time disassembly of various components is benefited, washing work is easy, and subsequent drainage work is ensured to go smoothly.