Abstract: In the paper, three kinds of lactic acid bacterial strains, Lactobacillus plantarum XN7, Lactobacillus acidophilus XM3, Lactobacillus rhamnosus XN9, were added in the composite fermentation of garlic, and flavor, active ingredients and microbial population changes were analyzed.The results showed that after 30 days of fermentation the smell of garlic gradually disappeared, fragrance appeared, and the taste significantly improved. After fermentation, p H decreased significantly and after10 days the p H of the solution remained at 4.The SOD activity increased at the beginning of fermentation, and maintained at a higher level, 250 U. At the beginning of fermentation, bacterial community was composed by the three kinds of lactic acid bacteria added, and accompanied by Enterobacter sp., Acinetobacter sp., Stenotrophomonas sp. and Bacillus sp., but Enterobacter sp., Acinetobacter sp., Stenotrophomonas sp. cannot be detected at the end of the fermentation, only three kinds of lactic acid bacteria and Bacillus sp.can be detected.The paper provides a reference for the production of fermented garlic.