The coupled copper ion transport through bulk and supported liquid membranes containing Acorga P-50 as carrier has been examined. The influence of membrane material (organic solvent, carrier concentration, polymeric support) aqueous donor (initial copper concentration) and acceptor (acid concentration) phase compositions has been established. It was found that copper ion fluxes through supported liquid membranes change in the same way as bulk transport fluxes under the influence of the various external factors studied, independently of kinetic regime used. A new method is proposed for estimating diffusion layer thickness in bulk liquid membranes and for characterizing unknown porosity of polymeric supports.