Three unique complexes were synthesized by interacting the antibiotic cefradine (Cefra) with some biological metal ions such as Mn(II), Fe(III) and Ni(II) in presence of 1,10- Phenanthroline monohydrate (Phen) in 1:1:1 molar ratio. The complexes were characterized by elemental analyses, spectroscopic techniques (FT-IR and UV-vis), X-ray diffraction (XRD), thermal analyses (TG-DTG), molar conductivity and magnetic moment. The molar conductance data supporting that all complexes were electrolyte confirming 1:2 for Fe(III) and 1:1 electrolytic for bivalent metal ions. The infrared data showed that Cefra interacted as tridentate ligand with metal ions via nitrogen of primary amine, two oxygen atoms, one of the carbonyl group of β-lactam ring and another one of carboxylic group while, Phen chelated through two nitrogen atoms. Magnetic moments and electronic absorption spectra data supporting an octahedral structure for our complexes. The decomposition mechanisms for Cefra, Phen and their complexes using TG and DTG were done. The average crystalline size (Cs), Full Width at Half Maximum (FWHM), dislocation density (D) and the nature of the compounds (crystalline or amorphous) were determined using XRD which indicted that Mn(II) and Fe(III) complexes were crystalline but Ni(II) complex amorphous in nature. The biological activities for all compounds were examined against some bacterial strains (positive and negative grams) and fungal strains. The data revealed that, the tested complexes have significant efficacy more than Cefra and Phen which may be used as better bactericides and fungicides.