BACKGROUND Adenoid hypertrophy is one of the main causes of upper airway obstruction and Obstructive Sleep Apnoea (OSA) in children. Studies have shown that administration of mometasone furoate aqueous nasal spray significantly improved oxygen saturation in children with sleep-disordered breathing. The aim of this study is to evaluate the effect of mometasone furoate aqueous nasal spray on oxygen saturation measured through nocturnal pulse oximetry and quality of life in children with sleep-disordered breathing due to adenoid hypertrophy. MATERIALS AND METHODS Eighty children suspected of having sleep-disordered breathing due to adenoid hypertrophy, whose parents were not willing for surgery (Adenoidectomy) were enrolled in a non-controlled clinical trial. Quality of life questionnaire was distributed pre-and post-interventional and the symptoms were scored depending on its frequency of occurrence. Pre-and post-intervention x-ray nasopharynx taken. Pre-and post-intervention nocturnal oxygen saturation monitoring was done and Oxygen Desaturation Index (ODI) as well as desaturation events were recorded. Data was analysed using paired student t-test and Wilcoxon's Signed Rank Tests. RESULTS Out of the 80 study population, 43 were males (53.8 %) and 37 were females (46.2%). Age distribution of the population ranged from 3 to 10 years with a mean age of 6.2 years. The study showed a strong positive correlation between grade of adenoid size and ODI (r -0.790; p < 0.001). All the pulse oximetric parameters improved significantly after drug administration (p < 0.001). There was a significant improvement in the quality of life of these children after the treatment. CONCLUSION The study revealed mometasone furoate aqueous nasal spray therapy leads to significant reduction in adenoid size and gives symptomatic relief for children with sleep disordered breathing. It can be recommended as the prime medical treatment modality for children with sleep disordered breathing, as it substantially reduced the morbidity and health care utilisation by these children.