A disposable diaper (10) includes a skin-surface-side sheet (50) arranged at a skin-contact surface-side of a wearer a non-skin surface-side sheet (60) arranged at a non-skin-contact surface-side of the skin-surface-side sheet an absorber (40) and a waistline retaining unit holding the disposable diaper onto the body of the wearer .the leg stretching units (75) are arranged on the inner side in the product longitudinal direction from diaper ends that configure the outer circumference of the disposable diaper or the inner side in the product widthwise direction from the diaper ends. A part of the waistline retaining unit is arranged in at least one of a first region (R1) on an outer side in the product longitudinal direction from the ends of the leg stretching units, and a second region (R2) on an outer side in the product widthwise direction from the ends of the leg stretching units. A joint region (65) where the skin-surface-side sheet and the non-skin surface-side sheet are joined is provided along the diaper ends in the first region and/or the second region.