Abstract: The objective of this study was to investigate the Cd2+ stress on the changes of phybiochemical characteristics in Acorus tatarinowii,which would be helpful both to the research of biological function of Cd2+and the biotransformation of Cd2+ by A.tatarinowii.Different concentrations of Cd2+were added to A.tatarinowii and measured phybiochemical characteristics on the 3d,7d and 11d respectively.The effects of different Cd2+ concentrations stress and different stress times on antioxidant activities,chlorophyll contents,membrane lipid peroxidation and Pro content in the leaves of A.tatarinowii were investigated by water culture experiments.The results showed that:(1) The activity of SOD increased with the increasing of Cd2+concentration on 3d,which was up to the peak at 50 μmol/L of Cd2+concentration and then decreased on 7d and 11d,but it was higher than the control.Except it increased first and then decreased with the prolongation of Cd2+stress time under 400 μmol/L,other concentration treatments increased.(2) The activity of POD increased with the increasing of Cd2+concentration on 3d and 7d,which was up to the peak at -00 μmol/L of Cd2+concentration and then decreased on 11d.With the prolongation of Cd2+stress time,POD activity decreased in all concentration treatments.(3) The activity of CAT increased first and then decreased with the increasing of Cd2+concentration in different stress times and increased with the prolongation of Cd2+stress time in all concentration treatments.(4) Chlorophyll content was up to the peak at 00 μmol/L of Cd2+concentration and then decreased in different stress times.Except it increased with the prolongation of Cd2+stress time under 400 μmol/L,other concentration treatments decreased.(5) MDA content and Pro content increased with the increasing of Cd2+concentration and the prolongation of Cd2+stress time.The analysis results showed that Acorus tatarinowii had a certain tolerance to Cd2+.