Objective: The nasal mucosal lymphocytes and nonlymphoid cells play a key role in the immune defence of the entire respiratory tract.The purpose of this study is to detect lymphocytes and nonlymphoid cells in the nasal lavage of 25 healthy adult by flow cytometric analysis and compare them with the cells in the peripheral blood.Methods: We studied 25 healthy volunteer students who did not have any upper respiratory diseases. Nasal Lavage was performed by instilling 8 ml of0.9% sterile saline solution, 4 ml in each nostril with the subject head tilted 30° backwards. Then, lymphocytes and nonlymphoid cells obtained from the nasal lavages were analysed flow cytometrically.Results: The flow cytometric analyses of nasal lavages were as follows: T helper cell/T suppressor cell ratio 2:1, total monoclear cell/monocyte ratio 11:1, T cell/B cell ratio 3.7:1, T cell/Natural killer cell ratio 5:1, T cell/active T cell ratio 5.8:1. The mean ratios were similar to the ratios of the peripheral blood (p<0.05).Conclusion : Lymphoid and nonlymphoid cells which are present in the nasal mucosa play an important role in the inflammatory response and nasal lavage analysis reflects the immunoregulation of both nasal mucosa and peripheral blood. Therefore flow cytometric analysis of lymphocytes and nonlymphoid cells in nasal lavage is a very practical and an efficent technique in clinical practise.