Flap parts (100) on the provided sanitary napkin (1) comprise: a narrowed section (100A) provided in the area corresponding, in the front-back direction, to wing parts (50) and widened sections (100B) provided in front and behind the edges of the wing parts (50), protruding further outwards in the width direction than the outer edges (100AE) of the narrowed section (100A). Widthwise, the outer edges (100AE) of the narrowed section (100A) are located further outwards than fold lines (L1) at which the wing parts (50) are folded over but further inwards than the outer edges (50WE) of the wing parts (50).