This disposable diaper (10) is provided with a sheet-shaped leg-encircling expanding/contracting section (100) that extends in the product lengthwise direction (L) at a region to which a leg-encircling indentation (35) is formed, and has a portion that can expand/contract along at least the product lengthwise direction (L). The ends in the product widthwise direction (W) of the leg-encircling expanding/contracting section (100) have a meandering shape in the product lengthwise direction (L)； the distance between a center line (CL) and the ends in the product widthwise direction (W) of the leg-encircling expanding/contracting section (100) changes from a front waist-encircling section (20) along towards a back waist-encircling section (30)； and there are a plurality provided each of inflection points at which the amount of change in distance shifts from increasing to decreasing, and inflection points at which the amount of change in distance shifts from decreasing to increasing.
