Abstract: The microbial community structure in mature Taorong-type Daqu was studied by high-throughput sequencing, and its correlation with the physicochemical properties of Daqu was analyzed. The results showed that a total of 83 bacterial operational taxonomic units (OTUs) were detected in Daqu. The main bacterial phyla included Firmicutes (79.15%), Proteobacteria (15.30%), Actinobacteria (4.05%), Cyanobacteria (1.42%), and others (0.08%). The dominant genera were Lactobacillus, Weissella, Pantoea, Leuconostoc, Kroppenstedtia, Saccharopolyspora, Pediococcus, Bacillus, Enterobacteriaceae_unclassified, Mitochondria_norank, Burkholderia and Cyanobacteria_norank. A total of 34 fungal OTUs were detected, among them, Ascomycota was absolutely dominant (99.19%). The dominant fungi were unidentified, Thermomyces, Thermoascus, Aspergillus, Rhizomucor, Wickerhamomyces and Kazachstania. The bacterial community in Taorong-type Daqu was much more diverse than the fungal community. The major microorganisms were predominant, and all identified microbial genera were significantly correlated with the physicochemical properties of Daqu. This study will be of great significance to guide the optimization of the production of Taorong-type Daqu and liquor.

Key words: Taorong-type Daqu; microbial community; high-throughput sequencing; correlation