Despite various methods of investigation, there are few reports as to the normal values of nasal airway resistance. A total of 56 adult subjects free of any nasal disease underwent nasal airway resistance measurement using active anterior rhinomanometry according to the guidelines of the international committee on standardization of rhinomanometry. Inspiratory and expiratory resistance was measured before and after application of a topical decongestant spray. This test was reproducible in that 46 of the subjects underwent a second study with resistance values quite close to that of the initial measurement. The upper range of the total inspiratory nasal airway resistance was 0.45 Pa s/cm3 before and 0.3 Pa s/cm3 after decongestant administration. There was no statistically significant difference between the inspiratory and expiratory resistance measurements. No correlation could be made between nasal airway resistance, age, sex, height or weight.