A new Schiff base 4-chlorophenyl)methanimine (6R,7R)-3-methyl-8-oxo-7-(2-phenylpropanamido)-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate= (HL)= C23H20 ClN3O4S) has been synthesized from β-lactam antibiotic (cephalexin mono hydrate(CephH)=(C16H19N3O5S.H2O) and 4-chlorobenzaldehyde . Figure(1) Metal mixed ligand complexes of the Schiff base were prepared from chloride salt of Fe(II),Co(II),Ni(II),Cu(II),Zn(II) and Cd (II), in 50% (v/v) ethanol –water medium (SacH ) .in aqueous ethanol(1:1) containing and Saccharin(C7H5NO3S) = sodium hydroxide. Several physical tools in particular; IR, CHN, 1H NMR, 13C NMR for ligand and melting point molar conductance, magnetic moment. and determination the percentage of the metal in the complexes by flame(AAS). The ligands and there metal complexes were screened for their antimicrobial activity against four bacteria (gram + ve) and (gram -ve) {Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus}. The proposed structure of the complexes using program, Chem office 3D(2006). The general formula have been given for the prepared mixed ligand complexes Na2[M(Sac)3(L)], M(II) = Fe (II), Co(II) , Ni(II), Cu (II), Zn(II) , and Cd(II). HL= C29H24 ClN3O4S, L= C29H23 ClN3O4S -.