【Objective】In order to design and find specific recognition and cleavage agent of DNA, two copper(Ⅱ) complexes,［Cu(AMB)₂Cl］Cl·4H₂O（complex 1）and［Cu(AMB)(phen)Cl］Cl·2H₂O（complex 2）（AMB = 2-aminomethylbenzimidazole, phen=1,10-phenanthroline）, were synthesized. 【Method】The two complexes were characterized by elemental analysis, IR, UV and molar conductivity. The complex 1 and complex 2 were assayed against gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and gram-negative bacteria(Escherichia coil and Salmonella typhi) by a double dilution method, and the interaction with ct-DNA was investigated by electronic absorption spectroscopy, fluorescence spectroscopy, viscosity measurements and agarose gel electrophoresis.【Result and conclusion】The complex 2 could interact with DNA by non-intercalation, while complex 1 by non-intercalation, and they cleave pBR322 DNA assisted by vitamin C involving the hydroxyl radical oxidation mechanism. The order of combination ability with ct-DNA and cleaving pBR322 DNA of the two complexes is complex 2＞complex 1, which is in accordance with the bacteriostatic activity.