PROBLEM TO BE SOLVED: To attach a support pillar in a cat tower, assembling and disassembling work can be performed in a short time and labor saving, and the assembling work can be performed accurately without malfunction and there is no possibility of collapse. A support column mounting structure is provided. SOLUTION: The structure is such that a support column for supporting and connecting between a pedestal and a flat plate P or between a flat plate P and a second flat plate is attached to a fixed part 8 fixed to the pedestal or the flat plate P and the fixing part 8 thereof. It has a fitting part having a receiving cylinder that is fitted and locked, and one end of a support column is fitted, a through hole 10 is formed in the central portion of the fixing part 8, and the through hole 10 is formed in the fitting part. A lock portion is integrally formed, which is fitted into the lock and is prevented from coming off by rotating. [Selection diagram] FIG. 7【課題】キャットタワーにおける支持柱の取付について、組み立てや分解の作業が短時間で省労力で実行でき、その組み立て作業にあって誤動作がなく精度よく実行することができ、崩れてしまう虞もない支持柱の取付構造を提供する。【解決手段】台座と平板Ｐ間、もしくは平板Ｐと第二の平板間を支持し、連結する支持柱を取り付ける構造で、台座もしくは平板Ｐに固定される固定パーツ８と、その固定パーツ８に嵌合してロックされ、支持柱の一端が嵌め付けられる受筒を有する嵌合パーツを有し、固定パーツ８の中央部位には透孔１０が形成され、嵌合パーツには、透孔１０に嵌め込まれ、回動することで抜け止めされ、ロック状態とされるロック部が一体に形成されている。【選択図】図７
