The nasal vestibule is a major site of resistance to airflow in healthy subjects. A high nasal resistance may increase snoring. Activation of the alae nasi and alar retraction reduce resistance to airflow and improve ventilation. The Breathe Right (BR) device has been proposed to reduce or eliminate snoring by improving nasal breathing. We assessed the efficacy of BR on sleep quality and snoring during 2 full-night polysomnographies, the first without and the second with BR. Ten non-apnoeic snorers were studied. Snoring was present during 22-98% of total sleep time during the control night. Ear-nose-throat examination disclosed a nasal valve anomaly in five subjects, objectivated by anterior and posterior rhinomanometry. Quality of sleep and snoring were not influenced by BR, even when different sleep stages were analysed separately. No difference in snoring index was found between snorers with or without nasal valve anomaly. We conclude that BR is ineffective in relieving snoring in non-apnoeic snorers.