To provide a disposable diaper which achieves a slim impression in appearance.SOLUTION: An absorbent core (11A) is folded into half, has a front side core part (11Af) and a rear side core part (11Ab), the absorbent core (11A) has a narrow width part (11fn, 11bn) whose lateral length is shorter than that of an upper part (11fu, 11bu), a belly side waistline part (20) and a back side waistline part (30) have a girth elastic member (23, 33). In a state of extending a leg surrounding elastic member (16) and a girth elastic member (23, 33), a vertical length of the narrow width part (11fn) in the front side core part (11Af) is longer than a vertical length of the narrow width part (11bn) on the rear side core part (11Ab), and the narrow width part (11fn) of the front side core part (11Af) has at least one compression part (E) having a prescribed lateral length, in an underpants type absorbent article (1).SELECTED DRAWING: Figure 2【課題】外観上すっきりとした印象を与えやすい使い捨ておむつを提供する。【解決手段】吸収性コア（１１Ａ）は、２つ折りされており、前側コア部（１１Ａｆ）と後側コア部（１１Ａｂ）を有し、吸収性コア（１１Ａ）は、上部（１１ｆｕ、１１ｂｕ）よりも左右方向の長さが短い幅狭部（１１ｆｎ、１１ｂｎ）を有し、腹側胴回り部（２０）及び背側胴回り部（３０）は、胴回り伸縮部材（２３、３３）をそれぞれ有し、脚回り伸縮部材（１６）及び胴回り伸縮部材（２３、３３）をそれぞれ伸長させた状態において、前側コア部（１１Ａｆ）における幅狭部（１１ｆｎ）の上下方向の長さは、後側コア部（１１Ａｂ）における幅狭部（１１ｂｎ）の上下方向の長さよりも長く、前側コア部（１１Ａｆ）の幅狭部（１１ｆｎ）は、左右方向に所定の長さを有する圧搾部（Ｅ）を少なくとも１つ有するパンツ型吸収性物品（１）である。【選択図】図２
