The purpose of this disclosure is to provide a disposable diaper which can be formed easily and which is configured so that the stomach side and buttock side of the disposable diaper have excellent fitting properties. The disposable diaper of this disclosure has the following configuration.The trunks-type disposable diaper includes an outer cover sheet, an absorption body, and a liquid impermeable leakage prevention sheet provided between the outer cover sheet and the absorption body, and is provided with a waist opening and a pair of leg openings. The disposable diaper is characterized in that the rear crotch region has a fold which is formed either by forming a protrusion section protruding to the clothing side and affixing the side edges of the protrusion section to the outer cover sheet, the protrusion section being formed by folding a part of the outer cover sheet in such a manner that the skin surface-side portions of the part of the outer cover sheet face each other, or by forming a protrusion section protruding to the skin surface side and affixing the side edges of the protrusion section to the outer cover sheet, the protrusion section being formed by folding a part of the outer cover sheet in such a manner that the clothing-side portions of the part of the outer cover sheet face each other.La présente invention porte sur une couche-culotte jetable qui peut être formée facilement et qui est configurée de telle sorte que le côté ventre et le côté fesse de la couche-culotte jetable présentent dexcellentes propriétés dajustement. La couche-culotte jetable de la présente invention présente la configuration suivante. La couche-culotte jetable de type slip de bain comprend une feuille de couverture externe, un corps dabsorption et une feuille de prévention de fuites imperméable aux liquides disposée entre la feuille de couverture externe et le corps dabsorption, et comporte une ouverture de taille et une paire douvertures de jambe. La couche-culotte jetable est c
