The early results of our laboratory showed that BA2380 protein may be related to the virulence of Bacillus anthracis (B. anthracis). The goal of this study is to knock out the BA2380 gene in B．anthracis A16D2 strain. The downstream and upstream sequences of BA2380 and spectinomycin resistance gene (spc) were obtained with polymerase chain reaction (PCR) respectively and used in the construction of plasmid pK2380usd for gene replacement. pK2380usd was introduced into B. anthracis A16D2 competent cells, and the BA2380 gene deletion was obtained by antibiotic screening and PCR identification. The results laid a foundation for the subsequent exploration of gene function.