Biosurfactants are surface-active compounds derived from microorganisms and offer several advantages over chemical surfactants, however the costs with substrates are high. In this study, papaya and passion fruit wastes were used as substrates to produce biosurfactant by a Bacillus subtilis strain. The submerged fermentation was carried out on shaker at 37°C, 200rpm for 96h. The strain was well adapted to the substrate using papaya waste with a maximum concentration of 1.0660 g.L-1 and emulsification index of 61.54%. These results were lower when the passion fruit waste was used as substrate: biomass concentration of 0.1380 g.L-1 and emulsification index of 54%.