Abstract:Shanxi aged vinegar is traditional brewing food with Daqu as starter in solid-state fermentation, the microorganisms of Daqu is important during Shanxi aged vinegar fermentation process. The aim of this study was to analyze the bacterial community structure and bacterial abundancein Daqu of Shanxi aged vinegar. Total DNA was extracted from Daqu of Shanxi aged vinegar, bacterial community was analyzed by Miseq high-throughput sequencing platform and 16S rDNA gene sequencing. The bacteria in Daqu were rich, including Firmicutes, Proteobacteria, Actinobacteria and Bacteroidetes at phyla level. Firmicutes and Proteobacteria were dominant phylum, their abundance were 69.67% and 29.17%, the proportion of Actinobacteria and Bacteroidetes were 0.86% and 0.28%, respectively. Bacilli was detected only in Firmicutes, Lactobacillus (32.82%) and Bacillus (29.45%) accounted for the main majority of the Bacilli. Gammaproteobacteria was detected in Proteobacteria, mainly including Pantoea (27.36%) and Acinetobacter (0.80%). Composition of Actinobacteria and Bacteroidetes were relatively simple, Actinobacteria and Flavobacteriia at class level, while Saccharopolyspora (0.59%) and Flavobacterium (0.27%) at genus level were found. These results clearly reflected the structure of bacterial community of Shanxi aged vinegar Daqu, and to help reveal the fermentation mechanism of Shanxi aged vinegar.