Provided is an elevator landing installation enclosure device having an enclosure (11) that accommodates elevator equipment. A lower ventilation hole (14) and an upper ventilation hole (15) are provided to the enclosure (11). The lower ventilation hole (14) is provided at a lowermost part of the enclosure (11) facing a floor surface (8). A foreign matter intrusion prevention part (19) that prevents foreign matter from intruding into the enclosure (11) from above the floor surface (8) is provided inside the lower ventilation hole (14). The foreign matter intrusion prevention part (19) includes a rising section (19a) that rises upward from the bottom of the enclosure (11), and a flat plate-shaped foreign matter removal section (19b) that protrudes from the top end of the rising section (19a) toward the lower ventilation hole side and that opposes the floor surface.