Abstract: An exhaust passage 53 includes: a first passage (high-speed passages 24b, 25b, and 26b); and a second passage (low-speed passages 24c, 25c, and 26c). A turbine housing 560 is connected to the exhaust passage 53 downstream from the collector 54. An exhaust device 100 of an engine 1 includes a valve (an exhaust variable valve 3) to open and close the first passage. A controller (an engine controller 7) closes the valve if an engine speed of the engine 1 is lower than a predetermined engine speed and opens the valve if the engine speed of the engine 1 is higher than or equal to the predetermined engine speed. The controller opens the valve even though the engine speed of the engine 1 is lower than the predetermined engine speed if performing the fuel cut control.