In a method for producing a water absorbent resin by drying a particulate hydrogel having a high solid content concentration (of 45% by weight or more, preferably 50% by weight or more, and more preferably 55% by weight or more), a method for efficient drying water absorbent resin having maintained/improved physical properties is provided. Disclosed is a method for producing a water absorbent resin, comprising: a polymerization step to polymerize an unsaturated monomer, and a drying step to dry a particulate hydrogel crosslinked polymer, which is obtained by micronization of a hydrogel polymer during or after the polymerization and which has a solid content concentration of 45% by weight or more, wherein, an amount of a peroxide in the particulate hydrogel crosslinked polymer to be dried in the drying step is 1 to 100 ppm relative to the weight of the solid content of the particulate hydrogel crosslinked polymer, and a drying temperature of the particulate hydrogel crosslinked polymer in the drying step is 160° C. or more.
