PROBLEM TO BE SOLVED: To provide an absorbent article which achieves both an increase in fitness in a back side region of the absorbent article and leakage prevention from a back side.SOLUTION: An absorbent article includes a surface sheet on a skin-contact surface side, a rear surface sheet on a non-skin-contact surface side, and an absorber between both sheets, and has a longitudinal direction partitioned into an abdominal side region arranged on an abdominal side of a wearer, a crotch region arranged in a crotch, and a back side region arranged on a back side and a width direction perpendicular to the longitudinal direction. The absorber has a thin part where basis weight of an absorber material is smaller than the circumference, the thin part extending from a back side end part of the absorber to the abdominal side. A plurality of the thin parts are aligned in the width direction, and a waist gathering part is arranged in a position overlapped with the thin part in the longitudinal direction.SELECTED DRAWING: Figure 1【課題】吸収性物品の背側領域におけるフィット性の向上と背側からの漏れ防止とを両立する吸収性物品を提供する。【解決手段】肌当接面側の表面シート、非肌当接面側の裏面シート、及び両シート間の吸収体を備え、着用者の腹側に配される腹側領域、股下に配される股下領域、及び背側に配される背側領域に区分される長手方向と、該長手方向に直交する幅方向とを有する吸収性物品であって、前記吸収体は、該吸収体の背側端部から腹側に延びる、周囲よりも吸収体材料の目付が小さい薄肉部を有し、該薄肉部は幅方向に複数並んでおり、前記薄肉部と長手方向において重なる位置にウエストギャザー部が配されている吸収性物品。【選択図】図１
