Lectin-binding patterns were observed with endothelial cells of human nasal mucosa according to the ABO blood group and they were obseved to find the marker lectin differentiating fenstrated from continuous capillary. Mucosal specimens were obtained from the inferior turbinate in 85 patients who underwent the intranasal ethmoidectomy or septoplasty. All specimens were fixed in 10% buffered formalin and embedded in paraffin. Serial sections, 4 μm in thickness, were made and stained with blood group specific lectins(DBA, GSI-B₄, UEA-I) and blood group non-specific lectins(SBA, PNA, RCA-I, WGA, Con-A) using avidin-biotin peroxidase method. Diaminobenzidine was used as a chromogen. The sections were counterstained with Mayer's Hematoxylin. Lectin-binding patterns were observed using Vanox-S light microscope. UEA-I, WGA, RCA-I, and Con-A were labelled irrespective of blood group. UEA-I reaction was positive in capillary of deep portion, venule, and sinusoid. But no reaction was noted in capillary near gland. These results suggest that lectin-binding patterns with endothelial cell of human nasal mucosa in non-specific to blood group and UEA-I can be used as marker lectin differentiating fenestrated and continuous capillaries. Further study using epon-embedding method and immunoelectromicrocsopy will be required.