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Bioremediation processes for the degradation of dyes from the textile industry have been of great interest, due to their capacity to decompose these contaminants without generating toxic products. Direct blue 71 contains three N=N azo groups and has an aromatic structure, making it a compound that is difficult to degrade. We evaluated the degradation potential of direct blue dye 71 by bacteria of the genus Bacillus. Bacteria isolated from sediments of hydrological basins were used, Gram staining and observation by scanning electron microscopy were performed. The kinetics of growth and biodegradation were performed in nutrient broth added with 100 mgL-1 of direct blue 71 incubating at 37°C and 200 rpm for 5 days, growth was determined by spectrophotometry at 600 nm and biodegradation at 575 nm. Phylogenetic analysis of the bacterial strains was carried out by amplifying the 16S rRNA gene. Two bacillary bacteria Gram positive were identified. Phylogenetic analysis identified strain ANCd110506 as Bacillus anthracis and strain ANHg310511 as Bacillus thuringensis, with a similarity index of 97.6 % and 100 %, respectively. Bacillus anthracis presented a biodegradation of 75.5 %, while the Bacillus thuringensis strain obtained a biodegradation of 67.9 % in 120 hours. [ABSTRACT FROM AUTHOR]