Provided is a method for producing a particulate water-absorbing agent that can reduce a re-wet amount of an absorbent body when applied to the absorbent body. The method for producing the particulate water-absorbing agent according to an aspect of the present invention includes the step of surface-crosslinking a water-absorbing resin powder with use of a surface-crosslinking agent, wherein the water-absorbing resin powder has a specific surface area index, expressed by formula (1) below, of not less than 1.5, and the surface-crosslinking agent has an apparent Hansen solubility parameter of 22.5 MPa 1/2 to 28.5 MPa 1/2 : specific surface area index = ( specific surface area of water-absorbing resin powder ) / 10 8 × D 50 2 where:
in formula (1), the unit of the specific surface area index is [1/kg], the unit of the specific surface area is [m 2 /kg], D50 denotes a mass average particle diameter, and the unit of D50 is [m].