This study was designed to evaluate the influence of nasal septal deviation on ostiomeatal complex (OMC). From April 1994 to February 1995, 32 patients with deviated nasal septum were investigated by high-resolution CT scan. The results showed that (1) 15 patients (15/32) were found to have ipsilateral or bilateral ostiomeatal complex disease (OMCD). The incidence of OMCD was related to the severity of the septal deviation; (2) measurement of uncinate process angulation and ethmoid infundibulum width in patients with OMCD was of limited value; (3) the relationship between septal deviation and OMC variation needed further study. It has been indicated that for patients with septal deviation coronal CT study is necessary to evaluate the degree of OMCD.