Synthesized from a new Neutral tridentate N2O Schiff base 4-(4- methoxybenzylidene)amino)-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one with amino acid ligand.forms stable complexes with transition metal ions such as Co (II), Ni (II), Cu (II), and Cd (II). The complexes were characterized on the basis of their Elemental analysis, molar conductivity, magnetic susceptibility data, IR, 1H-NMR, UV-Vis, XRD, Thermal Analysis (T.G, DTA, DSC), SEM, and Calculation Theoretical studies(DFT). Were used to characterize the complexes. The ligand acts as a tridentate chelating agent, According to physicochemical and spectral results, the ligand acts as a tridentate chelating agent. IR, UV-Vis., and magnetic susceptibility measurements all refer to an octahedral geometry. The general composition of all complexes [M(L)2] is (M=Co(II), Ni(II),Cu(II) and Cd(II), L=(K4-AMetB-Gly) The studies have led to the conclusion that, The coordination sites were established to be oxygen of the carboxyl COO- and two atoms nitrogen of the azomethine (CH=N) group based on the studies. The complexes non-electrolytic nature is verified by the lower conductivity data. The antibacterial activity of the ligand and its complexes was tested against Staphylococcus aureus, Escherichia coli, Klebsiella, and Psedomonas aeruginosa, it was found that these compounds show different activity of inhibition on the growth of the bacteria.