Abstract: A disposable diaper (1) includes a liquid permeable topsheet (2); a liquid impermeable back sheet (3); an absorbent member (4) interposed between the topsheet and bottom sheet; a fastening tape (10) for securing the diaper (1); and a release tape (30) to which an adhesive surface of the fastening tape is to be adhered. A tensile load of the back sheet (3) at 3% elongation in the transverse direction of the diaper falls within the range of 100 to 300 g/cm. A bulk softness of the back sheet (3) is 55 g or less. A peel strength required to peel the fastening tape (10) from the back sheet at 180.degree. is 400 g/cm or less. The time required until the fastening tape (10) and the back sheet (3) are peeled from each other under a load of 500 g is 10 minutes or longer. An outer surface of the back sheet (3) is not provided with a target tape.