Water-absorbent resin particles and method for producing same

A method for producing water-absorbent resin particles, comprising a step of polymerizing a monomer composition consisting of a water-soluble vinyl monomer (a1) and/or a vinyl monomer (a2) that turns into a water-soluble vinyl monomer (a1) through hydrolysis and up to 5 mol % of an additional vinyl monomer (a3) copolymerizable with the aforementioned vinyl monomers (a1) and (a2) based on the total number of mols of the vinyl monomer (a1) and the vinyl monomer (a2) and a crosslinking agent (b) in the presence of at least one organic main group element compound selected from the group consisting of organic iodine compounds having a tertiary carbon atom to which an iodo group attaches, wherein the monomer composition contains at least one of acrylic acid, methacrylic acid, a salt of acrylic acid and a salt of methacrylic acid as the water-soluble vinyl monomer (a1) in an amount of at least 75 mol % based on the total number of moles of the vinyl monomer (a1) and the vinyl monomer (a2), wherein the method includes a step of surface-crosslinking the crosslinked polymer (A).