An absorbent article that by sticking to the excretory part of the wearer without slippage of sanitary napkin, prevents any leakage of excrements, such as body fluid. The absorbent article is one comprising an absorbent article main body including at least surface sheet part (2) whose at least one area is permeable for liquid, disposed on one side in the direction of the thickness of the absorbent article and liquid-retaining absorbent part (4) disposed opposite to the surface sheet part (2) on the other side in the direction of the thickness of the absorbent article, and comprising, disposed on the other side of the absorbent article main body, belt member (10) arranged so as to extend along the longitudinal direction (LD,LD) of the absorbent article main body, the absorbent article shaped substantially longitudinally long. The belt member (10) on its side of at least one end of both ends thereof in the longitudinal direction (LD,LD) is provided with locking part (9f,9r).