Sauter mean drop sizes have been measured in a pulsed packed extraction column for two liquid systems with and without mass transfer conditions. The effects of pulsation intensity, phase flow rates, and interfacial tension on drop size have been investigated under a variety of operating conditions. The drop size is influenced mainly by pulsation intensity and interfacial tension. Significant, but weaker, are the effects of continuous and dispersed phase flow rates. A precise correlation is proposed for predicting mean drop size in terms of operating variables, physical properties of the liquid systems and mass transfer direction. Good agreement between prediction and experiments is found for all operating conditions that were investigated.