This disposable diaper (10) is provided with: a liquid-impermeable leakage-preventing sheet (55) provided at the non-skin-contacting surface side of an absorbent main body (15) and a pair of leg-encircling extending/contracting sections (100). The leakage-preventing sheet (55) has: an overlapping region (R1) overlapping the leg-encircling extending/contracting sections (100) in a plan view of the disposable diaper (10) and a non-overlapping region (R2) that is positioned to the outside of in the product lengthwise direction (L) of the overlapping region (R1) and that does not overlap the leg-encircling extending/contracting sections (100). The overlapping region (R1) is formed at the portion at which the distance in the product widthwise direction (W) between one of the leg-encircling extending/contracting sections (100) and the other of the leg-encircling extending/contracting sections (100) becomes the narrowest and at the central section in the product lengthwise direction (L), and becomes narrower towards the outside in the product lengthwise direction (L).【課題】股下部付近からの排泄物の漏れを防止しつつ、着用者の快適性をさらに高めた使い捨ておむつを提供する。【解決手段】使い捨ておむつ10は、吸収性本体15よりも非肌当接面側に設けられた液不透過性の防漏シート55と、一対の脚回り伸縮部100を備える。防漏シート55は、使い捨ておむつ10の平面視において、脚回り伸縮部100と重なっている重複領域R1と、重複領域R1の製品長手方向L外側に位置し、脚回り伸縮部100と重なっていない非重複領域R2を有する。重複領域R1は、脚回り伸縮部100の一方と脚回り伸縮部100の他方との間の製品幅方向Wにおける距離が最も狭くされている部分、かつ製品長手方向Lにおける中央部に形成されるとともに、製品長手方向L外側に行くに連れて狭くなる。【選択図】図2
