To provide a disposable sanitary product which is formed in such a manner that the disposable sanitary product can be fitted while preventing the side flaps from falling inward.

A liquid absorbing material 4 is filled in a space between a liquid-permeable front surface sheet 2 and a liquid-impermeable rear surface sheet 3. Both sides 5 in the longitudinal direction are formed into a gather 6 extending to a specified length with the central section as the center. At a location on the front surface sheet 2, which is on the inside of the gather 6, the side flap 7 for the prevention of a side leakage is provided under a standing state extending in the longitudinal direction. The side flap 7 is turned back to the outside, and the external surface at the approximately central location in the longitudinal direction is fixed to the front surface location of both sides 5 in the longitudinal direction.