PROBLEM TO BE SOLVED: To easily and accurately perform work when fitting a diaper to a diaper cup in a case of using an automatic excretion treatment device.SOLUTION: A diaper 100 provided with an opening part 590 includes an adapter 200 for a diaper cup 500, at an opposite side of a wearer side of the opening part, for use in an automatic excretion treatment device. The diaper cup suited for use in the diaper with the adapter includes an opening part, and a step 593 inside the opening part. An adapter fitting jig is provided for fitting the adapter to the diaper provided with the opening part.COPYRIGHT: (C)2015,JPO&INPIT【課題】自動排泄処理装置を利用する場合に、おむつをおむつカップに取り付ける際の作業を、簡単かつ正確に行う。【解決手段】開口部590が設けられたおむつ100の開口部の着用者側とは反対側に、自動排泄処理装置に用いるおむつカップ500のためのアダプタ200を設けると共に、アダプタを備えたおむつの使用に適した、開口部と開口部の内側に段差593を有するおむつカップと、アダプタを開口部が設けられたおむつに取り付けるためのアダプタ取り付け治具を提供する。【選択図】図8