A disposable diaper has a central elastic member formed along the lengthwise direction L so that the absorber can be curved to be convex in the inward direction, and a pair of side slits formed along the lengthwise direction L so that the absorber can be curved to be convex in the outward direction. A thickness of the absorber at the central portion and at the side edge portions are smaller than a thickness of the absorber at the middle portions.
