This disposable diaper (1) has leg expanding/contracting parts (10) in both side parts along a vertical direction X of a crotch part C, the leg expanding/contracting parts (10) each having, in order from a skin-facing surface side, an elastic member fixing sheet (5), elastic members (6), an inner-layer sheet (31), and an outer-layer sheet (32), the inner-layer sheet (31) and the outer-layer sheet (32) extending in the vertical direction X and being joined in a plurality of joining parts (7) disposed intermittently in the horizontal direction Y, the elastic members (6) being positioned between the elastic member fixing sheet (5) and the inner-layer sheet (31), and the elastic members (6) being disposed so as not to be superposed on the joining parts (7).本發明之拋棄式尿布(1)於胯下部C之沿著縱向X之兩側部具有腿伸縮部(10),腿伸縮部(10)自肌膚對向面側依序具有彈性構件固定片材(5)、彈性構件(6)、內層片材(31)及外層片材(32),內層片材(31)及外層片材(32)係於沿X縱向延伸且於橫向Y上間斷性地配置之複數個接合部(7)接合,彈性構件(6)位於彈性構件固定片材(5)及內層片材(31)間,且彈性構件(6)以不與接合部(7)重疊之方式配置。5‧‧‧彈性構件固定片材6‧‧‧彈性構件7‧‧‧接合部31‧‧‧內層片材32‧‧‧外層片材L1‧‧‧間隔L2‧‧‧距離W‧‧‧寬度Y‧‧‧橫向
