The invention discloses a ceiling filtering device comprising a plurality of filtering units. Each filtering unit comprises two strip-shaped support frames arranged along a horizontal direction, and two strip-shaped support frames arranged along a longitudinal direction; the support frames are crossed to define a filtering area, and support plates extend to the filtering area from the support frames; the ceiling filtering device further comprises filtering pieces which are arranged on the support plates, a buffer filling part is arranged between the filtering pieces and the support plates and used for expanding or contracting relative to the support plates according to the weight of the filtering pieces supported by the buffer filling part in a self-adaptive manner so as to fill intervals between the support plates and the filtering pieces.