A new series of transition metal Complexes of Cu(II), VO(IV), Mn(II), Co(II), Ni(II) and Zn(II) with a Schiff base derived from 2-AminomethylBenzimidazole and 4-chlorobenzaldehyde(1-(1H-benzimidazol-2-yl)-N-[4- chlorobenzylidene) methanamine-BCTM) were successfully synthesized. The complexes have been characterized using chemical analysis, spectroscopic methods (IR, UV-Visible, 1 H NMR and ESR), conductometric and magnetic data. According to these data, we propose an octahedral geometry to all the metal complexes. Antibacterial activity of the ligand and its metal complexes were studied against two gram negative bacteria: Escherichia coli, Pseudomonas aeruginosa, and two gram positive bacteria: Bacillus subtilis, Staphylococcus aureus. It has been found that all the complexes are antimicrobially active and show higher activity than ligand. The nuclease activity of the above metal complexes were assessed by gel electrophoresis assay and the results show that metal complexes can cleave pUC19 DNA in presence of hydrogen peroxide compared to the ligand.