A pulse flow-channel-variable turbine device includes a turbine housing (1) in which a turbine impeller and an air outlet are arranged. An exhaust manifold (6) is connected to the inlet of the turbine housing (1). An internal flow channel is arranged inside the turbine housing (1), and a turbine housing outlet is arranged on the internal flow channel close to the turbine impeller. The internal flow channel is divided into a left-side flow channel and a right-side flow channel by a middle partition board disposed therein. The left-side flow channel and the right-side flow channel are respectively provided with a cambered partition board which is fixedly connected to the middle partition board at one end and is arranged close to the turbine housing outlet at another end. The device divides the interiors of the exhaust manifold and the turbine housing into four different flow areas, and realizes an effective utilization of the engine exhaust pulse energy both under a high and a low operating conditions consequently.
