The heteronuclear polymeric complex. (Zn(teta)Ni(mu-CN)(2)(CN)(2)](n) (teta: triethylenetetramine). was synthesized and characterized by elementel analysis, FT-IR spectroscopy, thermal analysis and single crystal X-ray diffraction techniques. The complex crystallizes in the monoclinic system, space group P2(1)/c and in which the Zn-II ion exhibits a distorted octahedral coordination by one tetradentate teta ligand and two bridging cyano groups as a trans position, whereas the Ni-II ion has square planer coordination and is coordinated by four cyano ligands. The decomposition reaction takes places in the temperature range 30-600 degrees C in the static air atmosphere.