PROBLEM TO BE SOLVED: To provide an improved closing system of a cage accommodating a laboratory animal.SOLUTION: The improved closing system of a cage accommodating a laboratory animal projects, at an upper edge (21) of a cage base (2), a U-housing directing outside of the edge and housing a gasket (22) and has at least two latches (7) and projecting hooks (7) of the opposite sides thereto, wherein the gasket (22) has a lip (23) projecting from the upper edge and contacting with a side edge (24) of a top part (1) to bend, the side edge lies on the upper edge, the latches (7) are connected their one side (7) with the base (2) and have flexion creases (7") having decreased thickness and the projecting hooks (7) are suppressed in slots (11) of the top part (1). Thereby, the latches (7) are bent at the flexion creases (7") when used, and the projecting hooks (7) can be connected with or released from the slots (11).COPYRIGHT: (C)2007,JPO&INPIT【課題】実験動物を入れるケージの改良型閉鎖システムを提供する。【解決手段】本発明は、実験動物を入れるケージの閉鎖システムを提供し、ケージの基部(2)の上縁(21)にて、縁部の外側に向かうU字形ハウジングは、上縁から突出して、頂部(1)の側縁(24)と接触して曲がるリップ(23)を有するガスケット(22)を収容し、前記側縁が前記上縁と重なり、一方側(7’)が基部(2)に接続され、厚さが薄くなった屈曲線(7”)を有する少なくとも2つのラッチ(7)、及び頂部(1)のスロット(11)内に抑制される反対側の突出フック(7’’’)を有し、従って使用時にラッチが屈曲線(7”)で曲がり、突出フック(7’’’)がスロット(11)と係合するか係合解除することが出来る。【選択図】図2