Ferric citrate liposomes(FAC-Lip) and heme liposomes(Heme-Lip) were successfully prepared by a rotary-evaporated film-ultrasonication method. The release of iron liposomes were studied in vitro, and results showed that both iron liposomes had sustained-released properties, with Heme-Lip showing superior sustained-released over FAC-Lip. The liposome/water partition coefficients(P) were determined by equilibrium dialysis and the influences on P were evaluated, as well as the binding Gibbs free energy between FAC(Heme) and liposome. The results show that P initially increased and then decreased with increasing cholesterol content and the ratio of lipid to drug. The hydrogen and electrostatic interactions were largest when P was at its maximum. At the dialysis equilibrium, the binding Gibbs free energies(ΔG) of FAC-Lip and HemeLip were –12.7 and –18.2 k J mol–1, respectively.