Permeation of indium through an emulsion liquid membrane (ELM) containing diisostearylphosphoric acid (DISPA) as a carrier was carried out. First, the influences of the emulsifier (Span 80) concentration, the reaction temperature and the stirring speed during the permeation of indium on the membrane stability were studied. Indium ions were quantitatively extracted with the ELM under the optimum conditions from the viewpoint of membrane stability. Furthermore, the permeation mechanism of indium through the ELM was examined under various operational conditions. The permeation process of indium was controlled by the interfacial reaction between In(OH)(2+) and DISPA adsorbed at the interface and by the external aqueous diffusion of indium.