Abstract: The present invention is intended to sufficiently fulfill the supercharging function at the time of either of low speed running of the engine and high speed running and realizing output improvement or fuel expense reduction. The present invention has the engine 101 having the jet mechanism for directly jetting fuel into the cylinder 101a, the first turbo supercharger 104 for supercharging the engine 101 at the time of low speed rotation, the second turbo supercharger 105 for supercharging at the time of high speed rotation, the first and second exhaust control valves 106 and 107 for selecting exhaust paths relating to the first and second turbo superchargers 104 and 105 and controlling the exhaust gas flow rate, and the controller 114 for controlling the switching operation of the exhaust control valves 106 and 107 so as to realize lamination combustion or homogeneous combustion using the first and second turbo superchargers 104 and 105 according to the operation conditions of the engine 101.