We use two mesoscale simulation methods, dissipative particle dynamics (DPD) and self-consistent field theory (SCFT), to model interfacial tension in ternary oil/water/surfactant mixtures. For model systems where the oil is dodecane and the surfactant is a linear alkyl ethoxylate,;the two methods show a good semiquantitative agreement among themselves, and with experimental :data. We further. discuss the advantages and limitations of the two methods and their possible use for surfactant screening in specific industrial applications.