PROBLEM TO BE SOLVED: To provide a disposable diaper with excellent surface gap maintainability and easy production.SOLUTION: In a disposable diaper, a lower-layer absorber 23B has a slender lower-layer penetration part 60 which penetrates through the thickness direction and extends along the cross direction at least at the center of a crotch part C2 in the width direction, an upper-layer absorber 23A has an upper-layer penetration part 50 which penetrates through the thickness direction at least in a range corresponding to the lower-layer penetration part 60 in the cross direction, the upper-layer penetration part 50 is located above the lower-layer penetration part 60 and has a slender middle part 51 extending in the cross direction and overhang parts 52 hanging over both sides of the middle part 51 in a rear position in the width direction, and side edges of the overhang parts 52 are formed into a shape in which at least a part of the front side is positioned outward in the width direction as moving rearward.
