A disposable diaper includes: a main body having a liquid-permeable topsheet, a liquid-impermeable outer sheet an absorber provided between the topsheet and the outer sheet, and a gather. The gather includes a plurality of elastic members arranged in a width direction outboard of the absorber. The elastic members are fixed to the gather in a state where the elastic members are stretched in a longitudinal direction. A side flap is located in one of end portions of the main body in the longitudinal direction and projects outwardly beyond at least one of end portions of the main body in the width direction. A joint portion joins the side flap and the main body. In a spread-out state of the disposable diaper, an outermost elastic member among the elastic members is arranged outboard of the joint portion in the width direction.本發明提供一種,提昇對身體的緊貼性,並防止側漏的用後即棄式紙尿布。解決手段,本體(10)與背側側翼(20)在接合部(51、52)藉由HMA等的接著材互相接合。構成褶邊(13、14)的複數條橡膠之中,在本體(10)最外側的橡膠(123a、124a),是比接合部(51、52)更被配置在寬幅方向外側。42...卡止帶20B...自由端52...接合部11...端部10A...端部區域20...背側側翼21...端部51...接合部20A...自由端41...卡止帶14r...端部13r...端部22...端部10D...端部區域10...本體S2...區域S1...區域10C...端部區域14...褶邊13...褶邊14f...端部13f...端部31...端部54...接合部43...卡止部10B...端部區域30...腹側側翼32...端部12...端部53...接合部1...用後即棄式紙尿布123、124...橡膠
