PROBLEM TO BE SOLVED: To provide a production method of a water absorptive material derived from a natural material, having absorption performance of a water absorption amount of 10 g or more, per 1 g of resin.SOLUTION: A production method comprises: a step for drying a residue obtained by squeezing a sap from an oil palm stem and a step for separating a particulate solid content having a porous structure in which minute holes are congested, from the dried residue, thereby producing a water absorptive material. The particulate solid content is formed of a soft tissue of a wood part. The particulate solid content is obtained by separating an acicular sold content therefrom, by screening of the dried residue.SELECTED DRAWING: Figure 3
