Rhinomanometry was the most reliable method to evaluate the degree of nasal obstruction objectively. Nasal resistance, Respiratory resistance, and nasal cycle were studied with active anterior rhinomanometry and oscillation method. This study included 22 healthy persons(18 males, 4 females, ages 20 to 30 years, mean 25). The mask technique of active anterior rhinomanometry and oscillation method were used to collect data continuously(30 minute interval) on each subject for about 50 hours in sitting position. Also, we studied the correlation between the nasal resistance and respiratory resistance. The results were as follows : 1) The mean total nasal resistance was 4.7cmH₂O/LPS(SD±3.0) and the highest data was 9.8cmH₂O/LPS without the subject impression of obstruction in healthy adults. So, we thought that the symptoms of nasal obstruction would occur with total nasal resistance greater than 10cmH₂O/LPS at least, but we should make a comparison between this group and other pathologic group. 2) The correlation coefficiency was 0.63(Rt.), 0.69(Lt.), and 0.49(Total) between nasal resistance and respiratory resistance respectively with statistical significance(p<0.5). 3) We found that 77.3% of the subject demonstrated nasal cycle. The estimated mean duration of nasal cycle was 2.2 hours and the longest cycle was 4 hours and the shortest was 30 minutes.