Nasal mucociliary clearance is one of the most important function of the respiratory tract, providing protection against external stimuli. Adenoid vegetation is a factor causing abnormal nasal mucociliary clearance in children. To evaluate the effect of adenoidectomy, we measured nasal mucociliary clearance time with the saccharine method in 53 patients, before and after tonsillectomy with adenoidectomy or adenoidectomy alone from July, 1993 to January, 1994. And the patients were grouped as sinusitis and non-sinusitis patients. Measured saccharine transit time was showed no significant difference between sinusitis group and non-sinusitis group(p>0.05). After the operation, saccharine transit time was prolonged initially, but there was gradual decrease and from third week significant reduction in saccharine transit time(p<0.05) compared with that before operation. These data surggested that mucociliary function was improved after adenoidectomy.