Building ventilation structure

The utility model discloses a building ventilation structure, and particularly relates to the technical field of building ventilation, the building ventilation structure comprises a ventilation pipeline, an air inlet cover is arranged at one end of the ventilation pipeline, a fan is arranged at one end, close to the air inlet cover, in the ventilation pipeline, and a filtering assembly is arranged at the other end in the ventilation pipeline; the filtering assembly comprises a supporting frame, filtering plates are arranged on the two sides of the interior of the supporting frame, and an activated carbon filtering layer is arranged in the middle of the interior of the supporting frame and located between the two filtering plates. By arranging the positioning blocks, the positioning columns, the second springs, the positioning holes and the like, one ends of the positioning columns can be inserted into the positioning holes after the supporting frame is pushed into the ventilation pipeline, so that the support