Atopic dermatitis (AD) is a multifactorial, genetically determined disease with a chronic relapsing course and a predisposition to hyperimmunoglobulinemia E. Abnormal colonization of Staphylococcus aureus, Malassezia furfur, and Herpes Simplex plays a significant role in maintaining inflammation in AD. Objective — to determine the frequency of bacterial, mycotic and viral complications in a group of patients with moderate and severe AD. Materials and methods. From 2018 to 2023, 80 patients with AD (moderate and severe forms) aged from 1 year to 53 years (average age 14.6 years) were under our observation. Patients with a SCORAD index ≥ 25 were included in the study. To confirm the nature of the infectious complication, additional examination methods were used: microscopy, bacteriological culture, amplification methods of research, dermatoscopy, immunoenzyme analysis. Results and discussion. An analysis of the total number of relapses of AD during the year was carried out, depending on the age and gender of the patients. The largest number of relapses was observed in the age group from 6 to 10 years — 9.4 ± 0.6. The frequency of AD relapses had a certain correlation with the severity of the course of dermatosis — the SCORAD index increased to 31.2 ± 0.4 in the group of patients with the highest frequency of disease relapses (9.4 ± 0.6) per year and, as a result, increase in the frequency of infectious complications. The conducted analysis showed that each age group of AD patients had its own characteristic spectrum of bacterial, mycotic and viral complications. The most frequent infectious complications of AD observed in the examined patients were streptostaphyloderma (18.8 %), molluscum contagiosum (11.3 %), mycotic lesions (10.0 %), herpes infection (6.3 %), Coxsackie virus (3.8 %), EBV infection (2.5 %). Conclusions. As a result of the clinical study, it was established that infectious complications in AD have age, gender, and topographic features that can change the course and prognosis of dermatosis. Against the background of reduced immunoreactivity, the risk of disseminated, lifethreatening forms of infections increases in patients with atopic dermatitis.