Quick plugging device for reserved hole of flue

The utility model discloses a quick plugging device for a reserved hole of a flue, which relates to the technical field of building construction and comprises a lower supporting mechanism, an upper supporting mechanism and a bearing platform template. According to the quick plugging device for the reserved hole of the flue, the top surface of the supporting platform template is attached to the bottom surface of the reserved hole needing to be plugged, and the inner side surface of an upper outer square pipe is attached to the outer side surface of the flue through threaded fit between a first screw rod and a lower threaded connecting plate; the inner side face of a lower inner square pipe is attached to the other outer side face of the flue through threaded fit between a second screw and an upper threaded connecting plate, the flue is extruded through cooperation between a lower extrusion block and an upper outer square pipe and cooperation between the lower inner square pipe and an upper extrusion block, and