The invention discloses an air inlet regulating device of a flow-passage-changeable turbine. The air inlet regulating device comprises a turbine shell, an executing device and an air inlet flow regulating device, wherein the executing device is in transmission connection with the air inlet flow regulating device; an exhaust gas bypass device is arranged on the turbine shell; and the executing device is in transmission connection with the exhaust gas bypass device. The executing device can control the air inlet flow regulating device and the exhaust gas bypass device at the same time, so as toselect the air inlet flow passage of the flow-passage-changeable turbine and control the air inlet flow and the exhaust gas bypass flow; and on the premise of ensuring the high-efficiency work of theturbine, the section-changeable function of a supercharger is realized, and the requirement for the whole-working-condition pressurization of an engine can be met.