The formation of emulsions by use of ultrasonication was Investigated, particularly for low-viscosity oils, The influence of the irradiated volume, power density, viscosity of the dispersed and continuous phases as well as the influence of the oil fraction on drop size were investigated. An equation based on turbulence theory can be used to predict the dependence of drop size on different process conditions and substance properties, Comparison with other methods shows that emulsification can be achieved with ultrasound just as efficiently.