An abstract is a brief summary of a research article, thesis, Schiff base ligand (L) was prepared by the reaction of 4-aminantipyrine with o-phenylenediamine, the prepared ligand characterized by Micro elemental Analysis, FT. IR, UV-Vis, and 1H,13C-NMR spectroscopy.complexes of Mn(II), Co(II), Ni(II), Cu(II) and Hg(II) with Schiff base and 1,10-phenanthroline (Phen) have been in-vestigated in aqueous ethanol with (1:1:1) (M:L:Phen). The prepared complexes were character-ized using flame atomic absorption, (C. H. N) Analysis, FT. IR and UV-Vis spectroscopic meth-ods as well as magnetic susceptibility and conductivity measurements. From the obtained data the octahedral structure was suggested for all complexes. The biological screening effects of the in-vestigated compounds were tested against the bacterial species (Staphylococcus aureus), (Esche-richia coli), (Bacillus) and (Pseudomonas) by the good diffusion method.