The novel Schiff base has been synthesized from 4-acetyl-3-methyl-1-phenyl-2-pyrazolin-5-one with 2-amino-4-phenyl thiazole. This Schiff base form complexes of type ML2.2H2O (Where M= Mn, Fe, Co, Ni and Cu). This Schiff base was characterized by elemental analysis, mass spectra, 1H NMR spectra 13C NMR spectra and F.T. IR spectra. Metal complexes were characterized by elemental analysis, Magnetic susceptibility, electrical conductance, electronic spectra, infrared spectra and TGA analysis. All the compounds were tested for their antimicrobial activity. The result indicates that the growth of the tested organism was inhibited by most of the compounds.