To make it easy to be inserted into nasal cavities, send enough air into respiratory tracts through the nasal cavities when inserted into the nasal cavities, and prevent them from falling out of the nasal cavities as much as possible.SOLUTION: A nasal cavity insertion tool 1 used during respiration through nasal cavities has: a right-side body part 2R and a left-side body part 2L internally having a hollow part 10 being cylindrical and extended from an end 2aa of one end side 2a to an end 2bb of the other end side 2b, and inserted into the nasal cavities； an opening 11 for opening the hollow part 10 to the outside in the end 2aa of the one end side 2a of the right-side body part 2R and the left-side body part 2L； an opening 12 for opening the hollow part 10 to the outside in the end 2bb of the other end side 2b of the right-side body part 2R and the left-side body part 2L； and a pressing part 13 provided at the other end side 2b of the right-side body part 2R and the left-side body part 2L, and being movable between a projected position laterally projected from the right-side body part 2R or the left-side body part 2L viewed from the other end side 2b and an overlapping position overlapped with the hollow part 10.SELECTED DRAWING: Figure 1【課題】鼻腔に挿入し易くし、鼻腔に挿入した際には鼻腔を介して十分な量の空気を気道に送り込むと共に、鼻腔から脱落することを極力防ぐこと。【解決手段】鼻腔を介して呼吸する際に使用される鼻腔挿入具１は、筒状であり、一端側２ａの端部２ａａから他端側２ｂの端部２ｂｂまで延設される中空部１０を内部に有すると共に鼻腔に挿入される右側本体部２Ｒ及び左側本体部２Ｌと、右側本体部２Ｒ及び左側本体部２Ｌの一端側２ａの端部２ａａにおいて中空部１０を外部に開放する開口部１１と、右側本体部２Ｒ及び左側本体部２Ｌの他端側２ｂの端部２ｂｂにおいて中空部１０を外部に開放する開口部１２と、右側本体部２Ｒ及び左側本体部２Ｌの他端側２ｂに設けられ、他端側２ｂから見て右側本体部２Ｒ又は左側本体部２Ｌよりも側方に突出する突出位置と中空部１０と重なる重なり位置との間で移動可能な押圧部１３と、を有する。【選択図】図１
