Emulsions generated in the liquid-liquid systems by means of mechanical mixing, ultrasound irradiation as well as both these methods simultaneously, are described and the experimental and analytical methods for evaluation of interfacial surface in such systems are depicted. Investigations were carried out for selected liquid-liquid systems where water was used as continuous as well as dispersed phase, maintaining constant dispersed phase hold-up ratio equal to 0.2. The dispersed phase droplet size distribution, enabled the interfacial surface evaluation. The dispersed phase droplet size and interfacial surface obtained experimentally, were compared with those calculated from available correlations.