A master's dissertation was discussed in the College of Science, University of Anbar on studying of some complexes of transition elements with selected dual-grant ligands and their biological effects by the postgraduate student, Mrs. Shahd Abdul Nasser Thabet. The dissertation aimed at preparing a new azo ligand and eight metal complexes from the reaction of salts of the elements (nickel and palladium) with mixed ligands and diagnosing the prepared complexes via using techniques including ultraviolet - visible, infrared, mass spectrometry, molar conductivity, magnetic sensitivity and careful analysis of the elements. The dissertation included finding easy and sensitive analytical methods for estimating the elements, where the prepared complexes gave a linear relationship subject to the Lambert-Beer law, calculating the detection limit, the quantity limit, Sandell sensitivity, the return ratio, the error rate and the standard deviation, as well as studying the biological effect of the complexes on two types of bacteria, which the complexes reviewed their ability to inhibit it.