A disposable diaper includes: a first inflection unit formed in an absorber and extending along a product widthwise direction; a second inflection unit formed in the absorber, extending along the product widthwise direction, and positioned towards a rear waistline unit from the first inflection unit; and a crotch unit formed between the first inflection unit and the second inflection unit. The size of the crotch unit along the product longitudinal direction is 30 mm or more and 150 mm or less in the natural state of the disposable diaper.