The interactions oil/water/rock may have strong influence in displacement of the oil in a reservoir. The capillary forces, responsible in part by the trapped oil, is one of the parameters that allow the optimization of water injection processes. During water injection, the high interfacial tension of water-oil decreases the flow capacity of oil and leave high saturations of this phase in the form of immobile and disconnected ganglia, in the regions already contacted by injected water. With the injection of surfactants, the interfacial tension decreases and some of the oil ganglia are mobilized. However, the interaction of salinity with the surfactant solution can bring important effects in the two-phase flow within porous media. The aim of this work is to study the effect of water salinity and concentration of surfactant in oil displacement process. In this study, the displacement tests were performed on Bentheimer sandstone of high permeability, for saline solution with and without non-ionic surfactant Lauryl Alcohol Ethoxylates- 8EO (L80), subjected to a temperature of 40 Celsius degree. The saturation and effective permeability of each phase at the end of imbibition and drainage were determined for the different water solutions. The results obtained show the variation in the efficiency of the displacement process, mainly influenced by the behavior of phases, the interfacial tension, concentration of electrolytes in solution (salinity) and in-situ emulsion formation.