Axial fan

The invention provides an axial fan. An axial fan includes: a motor having a central axis extending in a vertical direction; and an impeller having a plurality of blades and generating a flow of air by rotation of the motor about the central axis. The motor includes a stator portion and a rotor portion that rotates so as to face the stator portion. The impeller has an impeller cup fixed to the rotor portion. The impeller cup has a top plate portion that expands in a direction intersecting the central axis, and a side surface portion that extends downward from the top plate portion. The blade extends radially outward from the side surface portion, and has a trailing edge portion located rearmost in the rotational direction and a leading edge portion located foremost in the rotational direction. The blades are inclined from bottom to top from the trailing edge portion toward the leading edge portion, the leading edge portion is located above the top plate portion, and a wall portion is disposed between the lead