An engine includes a cylinder block, and a piston slidably mounted in a cylinder, with the cylinder block being formed with an exhaust passage leading to a combustion chamber through an exhaust port, a first scavenging port opened to an inner circumferential surface of the cylinder, a first communication passage formed from the first scavenging port in a radial direction of the cylinder, and a first scavenging passage formed with an opening on a bottom surface of the first communication passage, in which a side surface on a far side from the exhaust port forming the communication passage is formed towards the far side from the exhaust port in the combustion chamber, and the opening portion of the first scavenging passage and a landing portion formed in the periphery of the opening portion are formed at a bottom portion of the communication passage.