Chronic sinusitis is a common disease and its major symptom is mucoid or mucopurulent rhinorrhea. Up to now, it has been known that the main sources of glycoproteins in nasal secretion were goblet cells and acini of submucosal glands. But few studies had tried to quantify them, and there are no reports about the composition of mucous and serous acini in human. We investgated the composition ratio and the number of mucous and serous acini in patients with chronic sinusitis and normal subjects using AB (pH 2.5)-PAS and H & E stain. The results are as follows ; 1) Pure mucous acini were not noted. But mucous acini containing serous demilune and pure serous acini were observed. 2) The number of mucous and serous acini/1mm² of the inferior turbinate mucosa in patients with chronic sinusitis was 27.8±7.4, 36.2±5.0, respectively, which were not signfificantly increased than that of normal controls. 3) The composition ratio of mucous and serous acini in patients with chronic sinusitis was 42.6%, which was significantly increased compared to normal controls(27.3%). From these result, it is suggested that increased composition ratio of mucous acini may be one of the important morphologic changes responsible for mucoid rhinorrhea in chronic sinusitis.