An automatic cleaning drain structure includes a cover member, a base, a fan blades set and an object expeller set. The fan blades set is installed interior of a holding space of the base A wind power device extends from the object expeller set, and functional connection of the bearing between the fan blades set and the wind power device is used to effect rotation thereof, Accordingly, when a water flow flows past the fan blades set or the wind power device is blown by the force of wind, then a plurality of strip members of the object expeller set and a plurality of strip members of the wind power device rotate around the cover member about the bearing as center, thereby enabling the drain to achieve the objective of clearing away foreign objects to allow unimpeded water flow.