The many of metal ions-complexes of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II) , and Au(III) have been preparation and characterization using novel azo-Schiff base ligand derived from azo compound namely; (1,5-dimethyl-4-((4-methyl-1H-imidazol-2-yl)diazenyl)-2-benzyl-1,2-dihydro-3H-pyrazol-3-one ) with 2-amino pyrimidine. The structures of the new ligand azo-schiff base and their transition metal complexes are characterized using several techniques, including elemental analysis (C.H.N), electronic spectral, IR spectral studies,1HNMR,13CNMR, magnetic measurements, molar conductance and mass spectra The data show that these complexes have composition of [ML2]Cl2 where M = Co(II), Ni(II), Cu(II) ,Zn(II),Cd(II) and Hg(II), [MLCl]Cl2 where M=Au(III). The electronic spectral, and magnetic susceptibility data of the complexes suggest octahedral geometry of all complexes, except the Au(III) complex suggest a square planar geometry. In addition, these compounds were also the co-ordination sites are the azomethine nitrogen , azo nitrogen atom and imidazole nitrogen atom of the ligand. The ligand forms shap as natural tridentate manner. The biological screening effect of the Au(III) complex are tested against against several organisms , staphylococcus aureus, Esherichia coli, Aspegills niger, Aspegills flavus are reported . all data of biological activaity gave good results about good inhibition for complexes against microbs, the results show the highest inhibitory effect for complex.