Abstract: An axial fan includes: an impeller cup including a blade extending in a radial direction; a motor configured to rotate the impeller cup; and a housing accommodating the impeller cup and the motor. The housing includes: a casing portion covering an outer periphery of the impeller cup; a base portion supporting the motor; and a spoke portion connecting the base portion and the casing portion. The casing portion includes an inlet surface where air is drawn in, and an outlet surface where air is discharged. The casing portion is provided with a level difference portion at least partially in an inner peripheral surface of the casing portion on the outlet surface side.