To prevent the generation of an ignition delay when a scavenging pressure is low at an idle running time and a noise at a combustion time, in a two-cycle engine having a turbocharger and supercharger.

In this two-cycle engine having a scavenging port 1b communicating with an intake passage 2 in a cylinder 1a, a supercharging system 3 having a turbocharger 4 for supercharging an intake air by the utilization of an exhaust energy and a supercharger 5 for supercharging the intake air by the utilization of a engine rotation is provided in the intake passage 2 and the running state of the two-cycle engine is detected and the turbocharger 4 is controlled so that a back pressure is increased when the detected running state is an idle running state and the scavenging pressure in the idle running state is increased.