A sanitary napkin comprises an absorbing body. The absorbing body includes a fluid-permeable top sheet, a fluid-impermeable back sheet, and an absorber arranged between the top sheet and the back sheet. The napkin comprises a cover sheet for covering the surface of the top sheet. A circumferential edge region of the cover sheet is joined to the absorbing body. A plurality of flaps for fixing the absorbing body to underwear are sectionalized by a sectionalizing line in the central region of the cover sheet. At the time of use, the flaps are folded in the folding regions and are expanded so as to be fixed to the underwear. The flaps include a front flat and a rear flap that expand in the back-and-forth direction, and a left flap and a right flap that expand in the right-and-left direction.
