Zinc(ll) and copper(II) complexes with organic molecules are used in clinical medicine, e.g. (i) complex of zinc(ll) acetate with erythromycin is used for ache therapy, (ii) copper chelating agents were developed to treat Wilson disease, an autosomal recessive genetic disorder that causes copper accumulation primarily in the liver. In general, organic ligands can contribute to better transport of metal ions through the lipophillic regions of cell membranes. However, it is also possible that some metal complexes are not able to reach their site of action in sufficient concentration due to their decreased solubility. Antibacterial activity of model  [ZnCl₂(terpy)]  and  [CuCl₂(terpy)] complexes  was tested against seven strains of bacteria. The complexes were more effective against Gram-positive than Gram-negative bacteria. Between complexes, stronger effect was observed for [CuCl₂(terpy)] complex. The best effect was exhibited against Sarcina lutea (5 mg/ml). Escherichia coli showed low sensitivity to both complexes. Results of the study of the antibacterial activity suggest an absence of permeability of the complexes through the membrane proteins.