Obstructive sleep apnoea syndrome in children is characterised by recurrent complete and/or partial upper airway obstruction during sleep. Owing to the limited number of studies, the exact prevalence rate has yet to be determined, but an estimate as high as 1% to 3% has been suggested. Recent studies have shown that obstructive sleep apnoea syndrome in children is different from that in adults in its distinct clinical presentation, diagnostic criteria and treatment. Polysomnography is now recommended as the standard investigation for confirming the diagnosis. The majority of patients may benefit from removal of the enlarged tonsils and adenoids. Although nasal continuous positive airway pressure therapy has been the mainstay of treatment for adults with obstructive sleep apnoea syndrome, experience of its therapeutic effect on children is limited; recent reports are encouraging. Further efforts are needed in advancing both the clinical management of and research into this disorder.