A centrifugal fan includes: an impeller configured to suction or discharge air; a motor configured to rotate the impeller; a housing configured to accommodate the impeller and have a suction port through which air is suctioned by rotation of the impeller and a discharge port through which air is discharged by rotation of the impeller; and a cut-off portion formed on one side of the discharge port. A flow cross-sectional area of air flowing in the housing is gradually increased from the cut-off portion to the discharge port in an air flow direction, and a distance from a lower portion of the impeller to an inner peripheral surface of the housing in a rotational axis direction of the impeller is gradually increased in at least a portion from the cut-off portion to the discharge port in the air flow direction.