Objective To measure the effect of ephedrine on nasal patency. Methods Thirty-nine healthy adults(male 21, female 18) were enrolled in this study, the mean age was 37.9±11.5 years(range 20~61 years). Eccovision acoustic rhinometry was used to acquire the nasal cavity volume, minimum cross-sectional area and the distance between the nostril to minimum cross-sectional area before, 5 and 10 minutes after the use of ephedrine(NVb, NV5, NV10, MCAb,MCA5,MCA10, MDb, MD5, MD10), and acquired the difference values and variational rate(ΔNV5, ΔNV10, ΔMCA5, ΔMCA10, ρNV5, ρNV10,ρMCA5, ρMCA10). Results 1 NV5, NV10, MCA5,MCA10, MD5, MD10 were significantly different from NVb, MCAb MDb respectively. NV5 and NV10, MCA5 and MCA10 MD5 and MD10 were significantly different; 23.1% of the nasal cavity NV5 and MCA5 were smaller than NVb and MCAb. 2 ΔNV10 and ρNV10 were significantly bigger than ΔNV5, ρMCA5. 3 There was significant differences between men and women in NVb, NV5, NV10, MCAb, MCA5, MCA10, but there is no significant difference in ΔMCA5, ΔMCA10, ΔNV5, ΔNV10, ρMCA5, ρMCA10, ρNV5, ρNV10. 4 ΔNV5, ΔNV10, ρNV5 and ρNV10 were significantly correlated with age, but ΔMCA5, ΔMCA10, ρMCA5, ρMCA10 were not significantly correlated with age. Conclusion Acoustic rhinometry can be used to improve the accuracy of the ephedrine test, the results acquired at 10 minutes after using ephedrine were much better than those obtained at 5 minutes. The effect of ephedrine on nasal patency was not significantly different between men and women, and it has a decreasing trend with age.