Provided is an absorbent that has excellent water-retention capacity and gel strength and is environmentally friendly. A water absorbent comprising cross-linked naturally derived polymers and biomass nanofibers, characterized in that the cross-linked naturally derived polymers and biomass nanofibers form particles, and the biomass nanofibers are present inside the particles. The water absorbent can be manufactured by dissolving the naturally derived polymers, dispersing the biomass nanofibers in the resulting solution, adding a cross-linking agent to the liquid dispersion and cross-linking the naturally derived polymers, wet-granulating the resulting hydrogel, and dewatering and then drying the hydrogel.
