PROBLEM TO BE SOLVED: To provide an absorbent article having an excellent permeation rate, and water-absorbent resin particles and an absorbent body giving the absorbent article. An absorbent article (100) includes an absorbent body (10), the absorbent body (10) contains water-absorbent resin particles (10a), and in the water-absorbent resin particles (10a), a compacted bulk density is 0.500 g/cm3 or more, The amount of change in compacted bulk density is 0.020 g/cm 3 or more when moisture is absorbed at a temperature of 30° C. and a relative humidity of 80% for 1 hour. [Selection diagram] Figure 1【課題】優れた浸透速度を有する吸収性物品、並びに、当該吸収性物品を与える吸水性樹脂粒子及び吸収体を提供する。【解決手段】吸収性物品１００は、吸収体１０を備え、吸収体１０は、吸水性樹脂粒子１０ａを含有し、吸水性樹脂粒子１０ａにおいて、固めかさ密度が０．５００ｇ／ｃｍ３以上であり、温度３０℃、相対湿度８０％で１時間吸湿させたときの固めかさ密度の変化量が０．０２０ｇ／ｃｍ３以上である。【選択図】図１
