A method for producing a water-absorbent resin including the step of subjecting primary particles obtained by a first-step reversed phase suspension polymerization to agglomeration according to a second-step reversed phase suspension polymerization, each step using an internal-crosslinking agent-added water-soluble ethylenically unsaturated monomer, characterized in that A and B satisfy the relationships of:andwherein an amount of the internal-crosslinking agent added in the first-step monomers, based on 100 mol of the water-soluble ethylenically unsaturated monomer used in the first step, is defined as A mol, and an amount of the internal-crosslinking agent added in the second-step monomers, based on 100 mol of the water-soluble ethylenically unsaturated monomer used in the second step, is defined as B mol. According to the method of the present invention, a water-absorbent resin having excellent flow-through property, an absorbent material and an absorbent article containing the water-absorbent resin can be provided.