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Distilled grain waste (DGW) is a major waste eluted from Chinese spirit-making process.Composting can convert DGW into a sanitized,stabilized and mature product for use as fertilizer or soil amendment.Since low pH in fresh DGW (about 3.5) is one of the main problems associated with composting of DGW,we first adjust the initial pH to 5 by adding lime.Then,composting test using pH-adjusted DGW was carried out.The results showed that volatile total solids (VTS) degradation mainly occurred during the first 23 days,and the highest VTS degradation efficiency was about 39.8% at the end.The raw material was not suitable as a fertilizer due to its high volatile fatty acids (VFAs) concentration.However,the composting process produced remarkable results;the physicochemical properties indicated that matured compost was obtained within 65 days of the composting process,and the final N concentration,NO3-concentration,and the germination index (GI) at the end of the composting process was 16.6 g/kg-TS,6.1 g/kg-TS,and 65.4%,respectively.The microbial communities through the composting processes were analysed by 16S rRNA gene high throughput sequencing on the Illumina Miseq platform.The sequence analysis at phylum taxonomic levels indicated that the main bacterial phyla including Firmicutes,Proteobacteria,Actinobacteria,Bacteroidetes,[Thermi]and Chloroflexi were found,and fungi phyla including Ascomycota and Basidiomycota were found in composting,being more or less abundant depending on the composting phases.Proteobacteria and Ascomycota were the dominant bacterial and fungi phyla in raw material,respectively.Firmicutes was the dominant bacterial community,and Ascomycota was the dominant fungi community at thermophilic phase.Relative abundance in Actinobacteria and Ascomycota gradually increased at mature stage,indicating that they probably play important roles during the maturation process.The redundancy analysis results shows =that the evolution of temperature,soluble total organic carbon,VFAs,total carbon content,pH,electrical conductivity and NH4+ have significant influence on the structure of bacterial community,but the structure of fungi community is strongly affected by NO3-,NH4+ and moisture content.These results demonstrate the feasibility of composting using DGW after pH adjustment,and reflect the evolution of physicochemical properties and the microbial communities involved in the composting process.