This study was designed to analyze normal nasal respiratory resistance in prepubertal children. The subjects consisted of 30 prepubertal children (male: 15, female: 15). The mean age was 11.4 years in male children and 11. 5 years in female children. The results were as follows: 1. The normal nasal respiratory patency was lower than the normal values from RION corp. 2. The normal nasal respiratory airflow rates showed no sexual differences. And there were no differences between inspiration and expiration. 3. Before and after use of nasal decongestants, there were no significant differences of normal nasal respiratory airflow rates and after the administration of nasal decongestants, nasal respiratory patency manifested lower variability. 4. The normal nasal respiratory resistance without nasal decongestants at 150 Pascal in inspiration was 0.30 Pa/cm<sup>³</sup>/sec (±0.07) and peak nasal inspiratory airflow rate was 1016.83cm<sup>³</sup>/sec (±223.89). 5. The normal nasal respiratory resistance with nasal decongestant at 150 Pascal in inspiration was 0.25 Pa/cm<sup>³</sup>/sec (±0.05) and peak nasal inspiratory airflow rate was 1148.33cm<sup>³</sup>/sec (±234.29).