In this study，the binding mode of a synthesized copper（Ⅱ） complex of 2-hydroxy acetophenone（HAP），［Cu（HAP）2］（1），to calf thymus DNA（ct-DNA） as biomolecular target was discussed by UV-Vis absorption，fluorescence emission and circular dichroism spectra，as well as DNA viscosity titration experiment.Results indicated that complex 1 binds to ct-DNA mainly via intercalation and exterior electrostatic interaction，in which intercalation can be ascribed to aromatic ring of HAP and the rigid planar structure of whole complex 1，while electrostatic interaction to DNA polyanionic backbone should be attributed to the cationic copper（Ⅱ） center of complex 1.The research results provided scientific evidence for the further exploration of the pharmaceutical activities of serial metal complexes of HAP.