Complex [CuL(NO 3)]NO 3·H 2O with acyclic ligand L bearing quinoline as terminal groups has been synthesized Structure analysis showed that the copper(Ⅱ) ion is in a distorted square pyramidal geometry with two quinoline nitrogen atoms and two thioether sulfur atoms in the equatorial sites and one of the nitrate oxygen atoms in the axial site The vacant axial site has weak interaction with the ethereal oxygen atom