A new hexadentate Schiff base ligand derived from condensation of 4-aminoantipyrine with aromatic diketone and thiosemicarbazide, and its metal complexes were characterized by elemental analyses, molar conductance, magnetic susceptibility measurement and spectral (electronic, IR, Uv-Vis, 1H NMR) studies. It has been originated that the Schiff base ligand with Co (II), Ni (II), Cu (II) and Zn (II) ions from mononuclear complexes on 1 : 1 (metal : ligand) stoichiometry. The conductivity data confirm the electrolytic nature of the complexes. The Co (II), Ni (II), and Zn (II) complexes show an octahedral configuration. Electronic absorption spectra of the Cu (II) complex suggest a square- planar geometry around the central metal ion. The IR spectral data suggest the involvement of sulphur and azomethine nitrogen in coordination to the central metal ion.