A fan includes an impeller rotatable about a rotation axis and having a plurality of rotating vanes, and a plurality of stationary vanes connecting an outer casing to a supporting body which supports a motor rotating the impeller. At least in a portion of each stationary vane in a radial direction, an axial distance between that stationary vane and one of the rotating vanes closest thereto and a slant angle of that stationary vane with respect to an axial direction increase as that stationary vane moves outwardly in the radial direction.