Sleep related breathing disorders (SDB) in children has a major negative impact on their neurocognitive development and should be identified and treated early as to decrease morbidity. Children do not usually present daytime fatigue and sleepiness like adults, but rather show abnormal behavior patterns and learning disabilities. The presence of sustained nightime snoring is a good screening toll for SDB. Polysomnography is the gold standard for diagnosis even though nightime oxymetry, with its high positive predictive value, can also be used. The most frequent SDB in childhood is sleep obstructive apnea syndrome (SOAS), which generally requires surgical treatment with adenotonsillectomy. Long term evolution of pediatric SOAS still has to be defined, as the role of other diagnostic tools such as outpatient polygraphy.