One of the main tasks of modern science is the search and synthesis of compounds with desired useful properties. Close attention should be paid to the study of mixed-ligand metal complexes containing metal ions and various ligands, which are biologically active molecules. In this work, the synthesis of complexes of phenylalanine and tryptophan with magnesium (II) and zinc (II) was carried out, some physical properties of the obtained substances were studied. The IR and UV spectra of the synthesized substances were obtained. In the IR spectra of the complexes, a shift and disappearance of some characteristic frequencies are observed. The disappearance of fluo-rescence, which is characteristic of individual amino acids, is observed in the UV spectra. An assumption has been put forward about the participation of metal in this effect. The physical properties of the synthesized substances have been studied, in particular, the melting points and the solubility of the complexes in water have been analyzed. There is a decrease in melting points compared to the starting materials, as well as a drop in solubility. Thus, the obtained results indicate the success of the synthesis of Mg(II) and Zn(II) metal complexes with phenylalanine and tryptophan. The practical significance of the synthesized substances lies in the use of metal complexes in medicine, agriculture and other branches of science and technology, as bioadditives, medicines or for physical research.