Abstract: The callus induced by different ploidy of Andrographis paniculata（Burn.F.） Nees was used as the test material, and colchicine was used to induce tetraploidy of Andrographis paniculata（Burn.F.） Nees seeds by adding allelopathic autotoxic substances to the culture medium for the callus induction of tetraploid and diploid of Andrographis paniculata（Burn.F.） Nees.The effects of cinnamic acid on the browning rate, cell fresh weight, superoxide dismutase（SOD）,peroxidase（POD）,catalase（CAT） activity and malondialdehyde（MDA） content of callus of different ploidy Andrographis paniculata（Burn.F.） Nees.,in order to provide a preliminary research foundation for screening excellent germplasm resources of Andrographis paniculata（Burn.F.） Nees against allelopathic and autotoxic substances.The results showed that treated with 0.05% colchicine for 48 hours, the induced survival rate of Andrographis paniculata（Burn.F.） Nees seeds reached 89%.After the plant morphology, stomata and chromosome number were tested, the tetraploid lines PZ-1,PZ-2,and PZ-3 of Andrographis paniculata（Burn.F.） Nees were determined, PZ-4,PZ-5,PZ-6,PZ-7,PZ-8,the number of chromosomes was 4x=96,and the diploid was 2x=48.After culturing in 1.00 mmol·L^-1 cinnamic acid callus induction medium for 7 days,the browning rate and MDA content of Andrographis paniculata（Burn.F.）Nees tetraploid callus were lower than those of diploid,while the fresh quality of callus,SOD,POD,CAT activities were higher than those of diploid,which showed that tetraploid had stronger resistance to cinnamic acid than diploid.Among them,tetraploid PZ-7 showed more remarkable excellent characteristics.