To obtain an efficient diesel oil-degrading bacterial consortium and monocultures, knowledge of the diversity of the microbial community present in soils contaminated with diesel oil, their metabolic features and capacity to degrade diesel oil are of paramount importance. One of the important properties of hydrocarbon-degrading bacteria is the production of surface-active agents (biosurfactants).These agents are small surfactant molecules that affect the reduction of the interfacial tension and amphiphilic macromolecules that stabilize the emulsion (Deleu et al., 1999). In this work we report the diversity of biosurfactant producing and hydrocarbon-degrading microbial communities of two soils polluted with diesel oil. Furthermore, we evaluated the emulsification capacity of the isolates.