Schiff base derived from 2-hydroxy-5-chloroacetophenone and 2-amino-4-phenyl thiazole with Complexes of Co(II), Ni(II), Cu(II) and Zn(II) have been synthesized and characterized on the basis of elemental analysis, Infrared, 1H NMR, molar conductance and magnetic susceptibilities analysis. The Schiff base acts as a monobasic bidentate ligand commonly coordinates through the oxygen atom of phenolic OH group and the nitrogen atom of azomethine group, which is confirmed by IR spectral data. All the complexes have been evaluated for their antimicrobial activity by agar cup-plate method against various organisms.