A disposable diaper 10 includes a sheet-like elastic element 100 provided in a rear waistline portion 30. The sheet-like elastic element 100 has a stretching portion 105 that can be stretched in a product width direction W. An absorber 40 includes a low rigidity portion 110, where the basis weight is lower than those in the other parts of the absorber 40 or an absorber core 40a does not exist, and a non-stretching portion 45 that is unstretchable in the product width direction W. The non-stretching portion 45 is provided at a crotch portion side from the stretching portion 105, and the stretching portion 105 overlaps at least a part of the low rigidity portion 110 in the plan view of the disposable diaper 10, and the width of the low rigidity portion 110 in the product width direction W widens towards the end at the side of the rear waistline portion 30 in a product longitudinal direction L.