In this study, 13 TetR genes (BbTetR1,…, BbTetR13) at whole genome level of biocontrol bacteria Brevibacillus brevis X23 were identified using bioinformatics methods for the first time. The results of basic property, gene structure and high-level structural analysis showed that the members of TetR gene family were conservative in evolution. The length of the gene sequences ranged from 477 to 681 bp, with 168 and 226 amino acids respectively. The molecular weights of the family proteins ranged from 1.9 × 104 to 2.57 × 104 and the isoelectric points were 4.84 to 7.77. According to the phylogenetic tree, TetR genes could be divided into three clades. Group I contained 5 members, group II 4 members, and group III 4 members; All BbTetR proteins contained a large number of α-helixes and their spatial structures were diverse. The results of transcriptome analysis showed that the expression patterns and levels of different BbTetRs in different growth stages were significantly different. BbTetR1, BbTetR5, BbTetR8 and BbTetR10 had higher expression in different growth stages of Bacillus brevis, suggesting that they may play an important role in protein expression regulation.