Sealing ring structure of a sinkhole

A sealing ring structure of a sinkhole, which is inlaid in the sinkhole to achieve bugproof and odorproof effects. The sealing ring structure includes a base seat, a diaphragm and a gum ring. The base is a ring body having a screen section formed with multiple perforations. The center and other portions of the screen section are respectively formed with holders. An upper end and a lower end of the base seat are respectively formed with a flange and a stepped skirt. The diaphragm is a gum-made thin disc having chucking bosses inserted in the holders to connect the diaphragm under the base seat with outer circumference of the diaphragm tightly attaching to the stepped skirt of the base seat. The gum ring is fitted around the base seat under the flange thereof. A middle portion of the gum ring is formed with a bight section. When the base seat is placed in the sinkhole, the gum ring is snugly watertight fitted in the sinkhole. The sealing ring can be directly placed in the sinkhole on a stepped shoulder section thereof instead of the conventional petal-type plastic ring to achieve a bugproof and odorproof effect.