To study the effect of hydrolyzable tannins (HT) on the growth performance and intestinal microflora of , HT was added to basic feed at concentrations of 0.1%, 0.2%, and 0.3%. After a 60-day feeding test, the growth performance of was determined and high-throughput sequencing was used to analyze the composition and variation of gut microbiota. The results showed that:(1) the rate of weight gain, specific growth rate, and condition factor of three experimental groups were significantly higher than those of the control group (P<0.05). (2) In total, 206192 optimized sequences were obtained from the four samples, with 542 operational taxonomic units. The intestinal microflora of in the control group contained a high proportion of Proteobacteria and Cyanobacteria, followed by Actinobacteria and Bacteroidetes. The dominant phyla in the experimental groups were Proteobacteria and Tenericutes. Compared to the control group, the proportion of Cyanobacteria, Actinobacteria, and Bacteroidetes decreased, whereas the proportion of Proteobacteria, Tenericutes, and Firmicutes increased in the experimental groups. (3) Rank-abundance curve and diversity analysis revealed that the species abundance and species evenness were higher in the experimental groups than in the control group. PCoA analysis showed that the microbial communities in the 0.2% and 0.3% groups were similar, but significantly different from those of the 0.1% group. Combined with growth performance indicators, we concluded that adding 0.1% HT to the diet might be most economical. In conclusion, dietary HT could significantly affect the intestinal microflora of and enhance its growth performance.