A dorsal side barrier is configured so as to stand up unintentionally when a diaper is used. This problem is solved by an underpants-type disposable diaper characterized by being provided with the dorsal side barrier which is unfolded so as to spread in a natural length state and which is turned up automatically when the diaper is stretched.

A sanitary product with three-dimensional cuffs includes an absorbent body and three-dimensional cuffs. The three-dimensional cuff is composed of a water-repellent thermal-bonded nonwoven fabric, one or more rubber bands, and a lining fabric. The water-repellent thermal-bonded nonwoven fabric is strip-shaped; its inner side edge is bent downward and outward to form a bent portion with an internal space. The outer bottom surface of the bent portion is adhered to the surface of the absorbent body, and the outer side edge of the water-repellent thermal-bonded nonwoven fabric is adhered to the outer edge of the absorbent body. The one or more rubber bands are adhered between the upper surface of the lining fabric and the top surface of the internal space of the bent portion via rubber band glue, and the lower surface of the lining fabric is separated from the bottom surface of the internal space of the bent portion.