Few mixed ligand complexes of Transition and Inner transition metals have been synthesized by reacting their metal salts with a substituted benzimidazole derivative, Omeprazole and RNA bases, uracil /adenine. All the complexes were synthesized in ethanolic medium and refluxed in reaction medium. The yield percentage ranging from 80-90%. The complexes are coloured solids and of the type [M(Ome)(Ade)2.2H2O)]SO4.xH2O.and [M(Ome)(ura).4H2O)]SO4.xH2O. They are characterized through elemental analyses , conductance measurements , spectroscopy (FT IR, Mass, 1H NMR and U.V). An IR spectrum indicates that all the ligands behave as bidentate ligand. Molar conductance studies indicates electrolytic behavior of these complexes. The metal complexes have been screened for their antifungal activity towards Aspergillus niger fungi. The result obtained is compared with that of parent drug. The result reveals that the metal chelates showed resistance as compared with parent drug.