PROBLEM TO BE SOLVED: To prevent an insect cage from falling down, and even if the insect cage falls on a floor or the like, the external pressure due to the fall can be dispersed and the impact can be absorbed. SOLUTION: The insect cage 10 is formed in a hollow spherical shape, and a plurality of ventilation holes 11b, 12b are formed in the peripheral walls 11a, 12a. The bug cage comprises a first hemisphere 11 having a circular first opening 11c and a second hemisphere 12 having a circular second opening 12c corresponding to the first opening. The second opening is aligned with the first opening and the second hemisphere is united with the first hemisphere to form a sphere. The hemispherical hinge portion 13 connects the second hemisphere to the first hemisphere so as to be relatively rotatable so that the first and second openings are combined to close the inside, or the first and second It is configured so that it can be changed to either an open state in which each opening is exposed and the inside is open. The hemispherical locking mechanism 14 that can be held in the closed state is provided on the first and second hemispheres. [Selection diagram] Fig. 1【課題】虫かごが倒れるということがなく、また虫かごが床等に落下しても、落下による外圧を分散させてその衝撃を吸収できる。【解決手段】虫かご10は、中空の球体状に形成されかつ周壁11a,12aに複数の通気孔11b,12bが形成される。この虫かごは、円形の第1開口部11cを有する第1半球体11と、この第1開口部に相応する円形の第2開口部12cを有する第2半球体12とを備える。第1開口部に第2開口部を合せ第2半球体を第1半球体と合体させて、球体状に形成される。半球体用ヒンジ部13が第2半球体を第1半球体に対して相対回転可能に連結することにより、第1及び第2開口部を合せて内部を閉止した閉止状態又は第1及び第2開口部をそれぞれ露出させて内部を開放した開放状態のいずれかに変更可能に構成される。上記閉止状態に保持可能な半球体用係止機構14が第1及び第2半球体に設けられる。【選択図】図1