BackgroundDiagnosis and treatment of obstructive sleep apnea (OSA) in infants and young children is challenging because of its clinical heterogeneity and lack of age‐specific guidelines.AimWe report the management and treatment outcome of OSA in children below 2 years of age. Treatment decisions were based upon the pattern of upper airway (UA) obstruction, clinical presentation and OSA severity.MethodsRetrospective, non‐randomized observational cohort study at a tertiary center. Children with OSA who underwent an UA evaluation (drug‐induced sleep endoscopy or direct laryngoscopy) were included.ResultsWe studied 100 patients, 57 boys and 43 girls, age 0.72 years (0.0–2.0) and OSA confirmed by polysomnography. Multilevel UA collapse was present in 26%, (adeno)tonsillar hypertrophy in 31% and 21% had laryngomalacia. Laryngomalacia was more common in children below 6 months of age and adenotonsillar hypertrophy was observed mainly in children >1.5 year of age. Surgical and nonsurgical treatment guided by UA findings, improved OSA severity at group level with a significant reduction (p < 0.001) in obstructive apnea/hypopnea index from 10.8/h (2.1–99.1) to 1.7/h (0.0–73.0), an improvement in mean oxygen saturation from 96.9% (88.9–98.4) to 97.4% (92.3–99.0), in minimal oxygen saturation from 85.4% (37.0–96.0) to 88.8% (51.0–95.5) and oxygen desaturation index from 5.1/h (0.2–52.0) to 1.3/h (0.0–47.8).ConclusionMultidisciplinary management of young children with OSA guided by the pattern of UA obstruction and OSA severity, reduces OSA severity. The pattern of UA obstruction changes in the first 2 years of life from a dynamic collapse to structural abnormalities.