Objective: To evaluate nasal ventilation in allergic rhinitis patients after nasal provocation with acoustic rhinometry., Method: Twenty AR cases were selected. Each one was assessed for the nasal cavity volumes (NCV), nasal airway resistance (NR), nasal minimal cross-section area (NMCA) and distance of nasal minimal cross-section area from nostril (DCAN) by using acoustic rhinometry before and after nasal provocation 1 hour and 6 hours later. The results were statistically analyzed., Result: After nasal provocation 1 hour 1 later, NCV and NR had a significant difference compared with before nasal provocation(P<0. 05), but NMCA and DCAN had no difference (P > 0.05). After 6 hours later, NCV, NR, NMCA and DCAN had a significant difference compared with before nasal provocation (P < 0.05). NCV,NR,DCAN had a significant difference between 1 hour later and 6 hours later after provocation (P < 0.05), while NMCA had no difference (P > 0.05)., Conclusion: The nasal ventilation in allergic rhinitis after nasal provocation had declined over time.