Using γ-ray irradiation method, propenyl monomer-chitosan copolymer hydrogel was synthesized with chitosan, acrylamide (AM), diallyl dimethyl ammonium chloride (DMDAAC), and N, N-methylene-bis- acrylamide as crosslinking agent. The influence of crosslinker MBA amount on water absorption and retention properties of propenyl monomer-chitosan copolymer hydrogel was studied. The results showed when the amount of MBA was lower with the absorbed dose of 2 kGy, equilibrium water absorption decreased with the increasing MBAs; when the amount of MBA was higher, equilibrium water absorption was less affected by MBA; the swelling ratio of hydrogel increased with time; non-Fickian diffusion law could be used to describe swelling kinetics of hydrogel at initial stage; with the increase of the MBA amount, initial water loss rate of the hydrogel increased, however, the maximum loss rate decreased.Cited