A plurality of joint portions (3) spaced apart from each other in the expansion / contraction direction (Df) are formed by a pair of sheets (1) and (2) on the first surfaces (1f) and (2f) of the pair of sheets (1) and (2). It is formed by welding to each other without using an adhesive, and holds the elastic member (F) and extends in a direction (Dp) intersecting the expansion / contraction direction (Df) of the elastic member (F). The stretchable sheet (10) includes a plurality of ridges (P) appearing between the plurality of joint portions (3) in a state where F) is contracted, and the width (W3) of the joint portion (3) in the stretch direction (Df). ) Is set to 0.2 mm or more and less than 1.0 mm.伸縮方向（Ｄｆ）に互いに離間した複数の接合部（３）は一対のシート（１），（２）の第１面（１ｆ），（２ｆ）において一対のシート（１），（２）が接着剤を介することなく互いに溶着されて形成され、かつ、弾性部材（Ｆ）を保持し、弾性部材（Ｆ）の伸縮方向（Ｄｆ）に交差する方向（Ｄｐ）に延びており、弾性部材（Ｆ）が収縮している状態において複数の接合部（３）の間に現れる複数の襞（Ｐ）を伸縮シート（１０）が備え、接合部（３）の伸縮方向（Ｄｆ）の幅（Ｗ３）が０．２ｍｍ以上１．０ｍｍ未満に設定されている。
