The present invention aims to provide a water-absorbing resin crosslinking agent which is excellent in safety and which can effectively crosslink a water-absorbing resin at low temperatures to produce a water-absorbing agent having a high water absorption capacity. The present invention also aims to provide a water-absorbing agent produced by crosslinking a water-absorbing resin with the water-absorbing resin crosslinking agent, and a method for producing the water-absorbing agent. The present invention may include a water-absorbing resin crosslinking agent containing a halohydrin compound having one halohydrin group represented by the following formula (1) in its molecule:wherein A represents a single bond or an alkylene group R1 represents a hydrogen atom or an alkyl group and X represents a chlorine atom or a bromine atom.
