A disposable diaper (1) has an absorbent body (40) disposed in, at least, an inseam region. A pair of side slits (46) designed to allow the absorbent body to curve convexly are formed in the inseam region. In a planar view, the intersection (P2) of the following lines is located rearwards of the side slits (46): a line (T1) tangent to a leg opening at the location of a halfway line (L1) that passes through the widthwise halfway point between a widthwise edge of a rear waist region and the widthwise center of a side curved section and a side-curved-section line (L2) that passes through the widthwise center of the side slits and extends in the front-rear direction.
