This study was conducted with the aim to isolation bacterial strains capable of antagonism to Cercospora arachidicola (Passalora arachidicola) causing brown spot in peanut. From 3 soil samples collected in the rhizosphere of peanut grown in Tay Ninh province, Vietnam, 10 bacterial strains were found having antagonistic action with Cercospora arachidicola. After 5 days of testing, the antagonistic efficiency of all isolates ranged from 33.33±1.28 to 60.183±0.927%. Studying the antagonistic mechanism showed that 5/10 isolates produced siderophore, 5/10 isolates were capable of decomposing chitin, 7/10 isolates capable of decomposing cellulase and 8/10 isolates proteolytic. Basing on the results of 16S rRNA gene sequence combined with morphological and biochemical characteristics, TN-TB 4, TN-TB 6 and TN-TB 12 were identified as Bacillus, representing the genera Bacillus amyloliquefaciens, Bacillus pasterurii, and Bacillus velezensis, respectively. These strains of antagonistic bacteria have the potential to produce probiotics
