An absorbable resin, for which a large amount of a plant-derived raw material can be used, and which has an excellent capability of absorbing an aqueous liquid, and has a good gel modulus and therefore can exhibit an excellent absorbing capability under pressurized conditions and an absorbable composition. An absorbable resin produced by binding an oxidized polysaccharide (A1) having a carboxyl group which may be neutralized with a neutralizing agent and/or a crosslinked product thereof (A2) to a poly(meth)acrylic acid (B1) in which at least one carboxyl group may be neutralized with a neutralizing agent and/or a crosslinked product thereof (B2) or an absorbable composition produced by mixing the component (A1) and/or the component (A2) with the component (B1) and/or the component (B2). The component (A1) has a weight average molecular weight of 2,000-10,000,000. The component (A1) has an acid value of 65-850 mgKOH/g. When the component (A1) has a carboxyl group which is neutralized with a neutralizing agent, the acid value of the component (A1) before the neutralization is 65-850 mgKOH/g.
