A novel azo schiff base dye (L) has been Synthesized a reaction of 5- [ 2-(5-nitro thiazolyl)azo] -2-amino -4-methyl pyridine (NTAPy) with 4-chloro benzaldehyde in alkaline solution . Anew series of complexes with Ag(I) ,Au(III) and Pt(IV) ions was Prepared forming chelate complexes . The structure of azo schiff base ligand and its metal complexes were characterized by different spectral technique such as1H-NMR, 13C-NMR, mass spectrum , FT-IR, electronic Spectra , C-H.N.S analysis , magnetic susceptibility ,atomic absorption and molar conductivity .The analytical data suggests the mole ratio [ M:L] was [l:l] for Ag(I)and Au(III) ions but [l:2] for Pt(IV) ion. The metal complexes of Au(III) and pt (IV) was l:l and l:2 electrolyte receptivity while the Ag(I) complex is non electrolyte . In this study the cytoxicity of Ag(I), Au(III), and Pt (IV) complexes on humn (PC3) breast cancer and normal cells were MTT assay .