Age-related (physiological) AH is an important problem in pediatric otorhinolaryngolo-gy. Since the beginning of the 70s, there has been an increase in the proportion of children with pharyngeal tonsil hypertrophy. Functional disorders of the oropharynx in children occupy the se-cond place based on their incidence (after disorders of the musculoskeletal system). In previous years, there has been an increase in the incidence and prevalence of obstructive sleep apnea syndrome (OSAS) among children. In most cases of pediatric OSAS, upper airway obstruction occurs from the nasopharynx to the oropharynx, caused by upper airway stenosis. Consequences of un-treated OSAS in children can be inattention and behavioral problems, daytime sleepiness, and in more severe cases are associated with a variety of comorbidities. The current review discusses the links between hypertrophied adenoids, craniofacial development and OSAS in children taking into account physiological and pathophysiological aspects as well as clinical evaluation of the problem.