A new macromolecule ligand and its mixed-valent Cu(I, II) and Fe(II, III) complexes have been prepared by using ethylenediamine as core and maleic anhydride as branched units and characterized by UV-vis, FT-IR, thermal analysis and X-ray photoelectron spectroscopy (XPS). The data obtained from these studies suggested that the coordinate bonds of N -> M, Cl -> M, Ph-OH -> M and H2O -> M have been formed and possible binding models are proposed for these complexes. The thermal analysis (TG-DTG) reveals that these complexes possess thermal stable property below 800 degrees C. (C) 2006 Elsevier B.V. All rights reserved.