The transport of-cobalt, nickel and copper through supported liquid membrane (SLM) containing as carrier trioctyl amine (TOA) has been studied. The effect of both carrier concentration and hydrodynamics of the system on the ion transport had been analyzed. The experimental data showed a high effect of boundary layers in the aqueous phases on the metal transport. A maximum in the curves of Co(II) and Cu(II) flux at ca 1.5 M of TOA was explained by the decrease of the diffusion coefficient of metal complex with the increasing concentration of the TOA carrier. Ni(II) ion was nor transported in the whole range of experimental conditions studied. This difference in transport behaviour was attributed to the fact that in chloride solutions; Co(II) and Cu(II) form anionic complexes of the type MeCl(4)(2-) while Ni(II) has do tendency to do so.