Sinusitis is an important cause of morbidity and one of the major sources of income loss. Anatomical variations of the nose have been reported to predispose to sinusitis. These variations include concha bullosa, nasal septal deviation and oversized bulla. The aim of this study was to determine the proportion and the distribution of concha bullosa in patients with chronic sinusitis and to determine the relationship between concha bullosa and age, sex, ethnicity. A cross-sectional study was conducted at the Department of Ear, Nose and Throat in Kuala Lumpur Hospital (HKL). Data was collected retrospectively using a pretested proforma. All patients who underwent Sino nasal surgery between January 1999 and December 2000 and whose preoperative CT scans were available were included in the study. The CT scans were reviewed. Analysis was carried out using Statistical Package for Social Sciences. Out of 146 patients who underwent sinonasal surgery between January 1999 and December 2000, 101 (69.2% preoperative CT scans of these patients were available and these were reviewed. The proportion of patients with concha bullosa was 49.5%. The results showed that there was significant relationship between presence of concha bullosa and age and sex. The overall mean age of patient with concha bullosa was 35.7 years (95% CI 12.1-39.3) and ranged from 11-years to 56-years. The mean age of respondents with concha bullosa was significantly lower than patients without concha bullosa 41.98 (95% CI 37.6-46.3; t-test = 2.221; df=99; p < 0.05). Concha bullosa was significantly more in females (66.0%) compared to males (chi2 = 4.465, df=1, p < 0.05). There was no significant relationship between presence of concha bullosa and ethnicity.