PURPOSE: The purpose of the study is to investigate the correlation between the symptoms and the incidence of anatomical variant without mucosal abnormality. MATERIALS AND METHODS: Out of 892 patients with CT performed for the evaluation of sinus disease symptoms between March 1991 and March 1993, we observed the anatomic variations in 82 symptomatic patients without mucosal abnormality(male:female=43:39, mean age 36. 4 years). The control group included 88 patients with facial bone CT performed for the evaluation of trauma during the same period while patients with recent paranasal sinusitis were excluded. (male:female=76:12, mean age 22. 4 years). The scouis were performed with 5-ram section thickness from posterior margin of sphenoid sinus to anterior margin of posterior ethmoid and then with 3 mm thickness from anterior margin of posterior ethmoid to anterior margin of frontal sinus. The artatomic variations included nasoseptal deviation, concha bullosa, Hailer cells, Agger nasi cells, etc. RESULTS: The anatomic variations were demonstrated in 71 our of 82 symptomatic patients(86. 5%), whereas they were seen 26 of 88 patients(29. 5%) in control group. CONCLUSION: Our data suggest that there is a possible causal relationship between anatomic variations and symptomas. Even though without accompaning mucosal abnormalities, anatomic variations could contribute simply to its symptomas. ^natomic variants may obstruct or narrow the airway, leading to turbulating air flow or interrupting ucociliary movement, and finally may produce a series os symptoms.