The present invention provides an air-cooled engine (10) has a fan cover (16) for covering a cooling fan (14). The cover (16) is composed of a fan-cover peripheral wall (44) for covering the outside of the cooling fan (14), and a top board (45) for closing off one end of the fan-cover peripheral wall (44). The fan-cover peripheral wall (44) has an internally disposed guiding duct (47) for guidingcooling air (Wi) from the cooling fan (14) to an engine main body (12). A first fastening member (42) secures a portion of the external part of the fan-cover peripheral wall (44) that is proximal to the guiding duct (47) to a casing (25) of the engine main body (12). A second fastening member (41) extends from the casing (25) and through the fan-cover peripheral wall (44), and secures a top board(45) in a portion that is at a distance from the guiding duct (47).