The thermosensitive hydrogels were prepared from the copolymerization of N-Isopropyl-acrylamide and N-vinyl pyridium tetrafluroborate(NVP.BF4) or N-methyl-4- vinyl pyridium methylsulfate (NMVP.CH3SO4) as cationic comonomers in the presence of methylene bisacrylamide(MBA) as crosslinking agent by means of γ-r and crosslinking agent on the properties of hydrogel especially the swelling ratio(SR) and sensitive temperature have been investigated The results show that theSRof the hydrogels will increase with the increasing the content of cationic monomer or decreasing the content of crosslinking agent.The sensitive temperature of the hydrogel will also increase with increasing the content of the cationic monomer but the content of the crossing agent seems to have no influence on it.