Introduction. Non-specific respiratory diseases, in particular, various clinical forms of bronchitis in young children and adolescents, are remaining not only a scientific problem, but also have medical and social impact. The aim of this work is to clarify the differential diagnostic criteria for different forms of bronchitis in children based on a comprehensive assessment of the results of bacteriological, clinical-radiological and bronchological examinations of patients. Materials and methods. The results of clinical observation and examination of 50 children with recurrent (35) and obstructive (15) bronchitis aged from 4 months to 3 years old are presented. According to age, all patients were divided into two groups. The first group consisted of children aged from 4 months to 1 year old (10), the second group included children aged from 1 to 3 years old (40). Smears taken from the mucous membrane of the anterior pharynx served as material for bacteriological examination. X-ray and bronchological examinations were conducted according to the indications, taking into account the severity and course of the disease. Conclusion. Our data indicate that the frequency of microbial sensitization in children with recurrent bronchitis is higher than in children with obstructive form of bronchitis that is obviously a favourable background for the development of infectiousallergic bronchial asthma. For patients with obstructive bronchitis, the state of bacterial polysensitization is more typical. Conducted studies indicate the feasibility of a comprehensive approach and evaluation of various clinical forms of bronchitis in young children, taking into account bacteriological, clinical-radiological and bronchological data that help to clarify the mechanisms of pathogenesis of this pathology and the use of rational methods of therapy.