Aim. The clinical guidelines are intended to provide information support for making decisions by gastroenterologists, general practitioners and internists that will improve the quality of medical care for patients with non-alcoholic fatty liver disease, taking into account the latest clinical data and principles of evidence-based medicine. Key points. Clinical guidelines contain information about current views on etiology, risk factors and pathogenesis of nonalcoholic fatty liver disease, peculiarities of its clinical course. Also given recommendations provide information on current methods of laboratory and instrumental diagnostics, invasive and non-invasive tools for nonalcoholic fatty liver disease and its clinical phenotypes assessment, approaches to its treatment, considering the presence of comorbidities, features of dispensary monitoring and prophylaxis. The information is illustrated with algorithms of differential diagnosis and physician's actions. In addition, there is information for the patient and criteria for assessing the quality of medical care. Conclusion. Awareness of specialists in the issues of diagnosis, treatment and follow-up of patients with nonalcoholic fatty liver disease contributes to the timely diagnosis and initiation of treatment, which in the long term will significantly affect their prognosis and quality of life.