Effects of ion implantation into dry cotton seeds on germinationpercentage, seedling survival rate and esterase isozymes, peroxidase isozymesand micronuclic cell rate in plumule were analysed. The results showed thatmicronuclic cell rate increased as ion implanting dose increased. After theimplantation, there were some changes with the activity and the numberof esterase isozymes and peroxidase isozymes. In the plumules treated by 4.different doses, the changes of the zymograms of esterase isozymes and peroxi-dase isozymes induced by the dose of 40 were largest. The difference betweenthe seedling survival rate derived from the seeds treated by the dose of 40and that of CK was insignificant.