In order to further prolong the processing industry of kiwifruit,taking kiwifruit as raw material,the fermentation conditions of kiwifruit Jiaosu were optimized by single factor tests,Plackett-Burman tests and response surface tests,and the removal effect of kiwifruit Jiaosu on 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS+),1,1-diphenyl-2-picrylhydrazyl(DPPH),hydroxyl free radical and Fe3+relative reducing capacity were analyzed.The results showed that the optimal fermentation process of kiwifruit Jiaosu was as follows:solid to liquid ratio 38∶100(g∶ml),bacteria(Saccharomyces cerevicae∶Lactobacillus plantarum∶Lactobacillus bulgaricus=3∶1∶1)inoculum 0.24%,sugar addition 12%,fermentation time 144 h,temperature 26.4 ℃.The superoxide dismutase(SOD)activity of the kiwifruit Jiaosu under the optimal conditions could reach 1 893.30 U/ml.The re-sults of antioxidant tests showed that the clearance rates of DPPH·,ABTS+·,·OH and Fe3+relative reducing capacity were 37.2%,80.13%,79.01%and 24.65%,respectively,which improved 7.98%,2.50%,2.41%and 3.58%respectively compared with that of before optimization.In conclusion,the SOD activity of the kiwifruit Jiaosu and the antioxidant activity were improved after fermentation process optimization.