Binary ceftriaxone metal complex of Cr (III) and five mixed metal complexes of [CrM(ceft.)2Cl(H2O)3], where M = Co(II), Mn(II), Ni(II), Cu(II), and Cd(II) were synthesized by a 1:1:2 molar ratio. FT-IR and UV-Vis spectroscopies, magnetic measurements, molar conductance, and microanalytical (C, H, and N) analysis were all used to describe the complexes. The shape, morphology, and size calculations have been examined using TEM and thermogravimetric analysis (TGA). The electronic absorption spectra and the magnetic moment values indicated the Oh geometry of the metal ions in the complexes. The ceftriaxone drug as a tetradentate ligand towards five metal ions through N (amino group) and O (triazine, βlactam carbonyl, and carboxylate groups). Several microorganisms have been tested for the complexes antibacterial activity, and the outcomes are contrasted with ceftriaxone's activity. From the results, all complexes show higher activity against Bacillus cereus and Escherichia coli except [CrCd(ceft)2Cl(H2O)3], which has nearly the same activity compared to ceftriaxone. All complexes show higher activity against pseudomonas aeruginosa than the activity of ceftriaxone. Moreover, they have lower activity against Micrococcus luteus, Sarratia marcescens, and Staphylococcus aureus.