Abstract: The fermentation conditions of compound fruit vinegar were optimizationed by response surface from hawthorn、red jujube and medlar, the changs of contents of amylose、FAA、flavonoid、polyphenols and clearence of OH·、DPPH· were studied in fermentation process of compound fruit vinegar.The results showed that the optimum fermentation conditions of compound fruit vinegar were 5.7% inoculum concentration, 6.9% incipient alcoholic strength, 6d fermentation time, the totel acidity of compound fruit vinegar was 4.32 mg /100 m L: the changes of contents of amylose and flavonoid were not markedness, the changes of contents of FAA, polyphenols and clearence of OH·, DPPH· were markedly increased. The clearences of OH·and DPPH·of compound fruit vinegar were increased after fermented.