A disposable diaper includes so that a sweat-absorbent sheet attached to the inner side of the diaper can maintain its sweat absorbing function during use of the diaper. The inner side of front or rear waist region constituting the disposable diaper is covered with a hydrophobic sheet and the sweat-absorbent sheet is bonded to the inner surface of the hydrophobic sheet. The hydrophobic sheet has a first sealing-free zone extending, inclusive of a first lower edge, in a circumferential direction so as to be left free from the inner side of the diaper and a first sealing zone extending above the first sealing-free zone and bonded to the inner side of the diaper. The sweat-absorbent sheet has a second lower edge extending in the circumferential direction above the first lower edge of the hydrophobic sheet, a second sealing-free zone extending, inclusive of the second lower edge, in the circumferential direction so as to be left free from the hydrophobic sheet and a second sealing zone extending above the second sealing-free zone and bonded to the hydrophobic sheet. A lower end of the first sealing zone is provided so as to lie below a lower end of the second sealing zone.