The paper presents the discoloration of a food dye (Brilliant Blue-BB) in aqueous solutions by ozonation. In order to establish the optimum parameters of this process and to reach its maximum efficiency, the influence of BB concentration, ozone dose, dye-ozone contact time and pH of aqueous solution were examined. The originality of the work consists in using low concentrations of ozone obtained from 99.5% purity oxygen. The obtained experimental data suggested that BB can be successfully discolored from aqueous solutions by ozonation. © 2019, Politechnica University of Bucharest. All rights reserved.