A disposable diaper (10) has an absorbent core (40a) having wide sections and a narrow section wherein the length of the absorbent core in the width direction is shortest. Marker patterns (M11, M12), which indicate positions on the absorbent core, are attached to a back sheet positioned more on a non-skin-contact surface side than the absorbent core (40a). The marker patterns are disposed at positions that do not overlap with the outer edge of the absorbent core in a product width direction. At least a portion of each marker pattern in an overlapping region where the absorbent core and the back sheet overlap is disposed in a region further to the outside in the product width direction than an imaginary line (FL1), which passes through the outer edge of the narrow section in the product width direction and extends in a product longitudinal direction.
