PROBLEM TO BE SOLVED: To provide a disposable diaper in which a proper dimension around each leg can be adjusted.SOLUTION: The disposable diaper includes a configuration in which in a state where a planar gather 80 formed on a leg surrounding portion of a side flap portion SF and elastically expanding/contracting in front/rear directions does not completely expand in the front/rear directions or in a state where the planar gather 80 does not expand, a suppressing member 81 for suppressing the expansion of the planar gather 80 is pasted on at least one of front and rear surfaces of the planar gather 80, a large number of cutting perforations 82 of the suppressing member 81 are separated as required, and the suppression is partially or totally released to increase the expandable length of the planar gather 80.
