This study explores the role of the nose in obstructive sleep apnea. If the nose acts as a Starling resistor, elevated nasal resistance may result in negative pharyngeal pressure that is of greater magnitude than the situation with normal nasal resistance. Large negative pharyngeal pressures could cause obstructive apnea. To test this hypothesis, nasal resistance studies were performed on 37 normal subjects and 63 patients with proven obstructive sleep apnea. The results suggest that although the patients had a significantly elevated nasal resistance, the increased nasal resistance did not correlate with parameters that predict the severity of obstructive sleep apnea. Although the nose probably contributes to sleep apnea, we conclude that nasal resistance is not a major factor in severe obstructive apnea.