Aim. Is the features of the microelement composition of saliva in diabetes mellitus. Objectives. To perform a systematic analysis of modern domestic and foreign literature sources to determine the main characteristics of the microelement composition of saliva, which determine the prospects for its use in the diagnosis of patients with diabetes mellitus. Methodology. The study was based on the search and study of original domestic and foreign articles on the study of the specifics of the microelement composition of saliva in patients with diabetes mellitus in the eLibrary, PubMed, Elsevier databases. The selection of relevant material was carried out by keywords. Results. Diabetes mellitus is a chronic disease of the endocrine system, related to immunological diseases, common in all countries of the world and tending to increase both morbidity and mortality. At the same time, mortality among people with diabetes mellitus can be caused not only by the disease itself, but also by a number of numerous possible complications. The definition of express diagnostics of the state of organs and systems in diabetes mellitus would be an effective method to prevent the development of severe stages of this serious disease and its complications. A number of studies published in periodic specialized scientific journals contain data confirming the possibility of using saliva in diagnosing the functional state of patients with diabetes mellitus. Thus, changes in the concentrations of chlorine and potassium in saliva were noted, relationships were found between the content of zinc, calcium, magnesium, phosphorus, beryllium, and boron. The obtained results are proposed to be used in the analysis of the risk of development of pathology of organs and systems in diabetes mellitus, including in the form of the development of carious lesions of the teeth, to identify disorders of carbohydrate metabolism and the implementation of metabolic control. Conclusions. Despite the relatively small number of studies on the possibility of using saliva trace elements as biomarkers of diabetes mellitus and its complications, an analysis of the literature on the relevance of studying the characteristics of the trace element composition of saliva in diabetes mellitus showed the prospects for performing these studies in terms of ease of analysis, rapidity of the method, its painlessness, non-invasiveness, uniqueness of the results obtained. © 2023, Endo Press LLC. All rights reserved.