In order to explore the diversity of pure cultured bacteria in the deep-sea sedimentary environment of the Indian Ocean, bacteria were isolated and identified from 12 sediment samples collected from the Indian Ocean. A total of 343 strains of bacteria were obtained by pure culture isolation method and 16S rRNA gene sequence analysis showed that these isolates belonged to Firmicutes, Proteobacteria, Actinobacteria, Bacteroidete and were divided into 5 classes, 13 orders, 26 families and 121 species under 39 genera. The dominant taxa were Streptomyces (separation rate is 16.53%) and Bacillus (separation rate is 8.26%), among which there were 12 potential new taxa. The results show that the deep-sea sedimentary environment of the Indian Ocean is rich in culturable bacteria and contains many new species; secondly, the isolation and culture methods are directly related to the bacterial species diversity obtained from marine sediments.