The present invention addresses the problem of providing a novel absorbent that comprises a water-absorbing cellulose-based fiber and a thermoplastic resin fiber, said thermoplastic resin fiber containing as a monomer component an unsaturated carboxylic acid or an unsaturated carboxylic acid anhydride, and has both a sufficient strength and a sufficient absorption property. The absorbent (4a) comprises a water-absorbing cellulose-based fiber and a thermoplastic resin fiber, said thermoplastic resin fiber containing as a monomer component an unsaturated carboxylic acid or an unsaturated carboxylic acid anhydride, wherein the mass ratio (the content of the water-absorbing cellulose-based fiber:the content of the thermoplastic resin fiber) is controlled to 90:10 to 50:50 and the density of the absorbent (4a) is controlled to 0.06 to 0.14 g/cm3.
