An intake passage of an engine includes a throttle valve, a supercharger, and a bypass passage connecting an upstream side with a downstream side of the supercharger and opening when the supercharger is not acting. When the supercharger is not acting, the intake passage generates forward flows in which intake air flows from the throttle valve toward the supercharger and bypass-directed flows in which the intake air is reversed due to blockage of forward movement by the supercharger and flows from the supercharger side toward a connection port, of the bypass passage, opening in the intake passage. An evaporated fuel introduction opening leading evaporated fuel produced in a fuel tank to the intake passage opens in a wall surface, on which the bypass-directed flow is generated, in the intake passage.