OBJECTIVE: To examine the age related volume change of the maxillary sinus in children by measuring the change of the height, weight, and depth using computed tomography (CT). METHODS: Children <18 years of age who underwent a CT Scan of the sinuses for reasons other than sinus related issues were included in the study. RESULTS: 139 patients were included (68 females and 71 Males) and the mean age of the patients was 9.6 +/- 5.4 years. The cohort was divided into three groups based on their ages - Age <6 years (n = 45), age between 6 and 12 years (n = 44) and age > 12 years (n = 50). Patients in each age group demonstrated an increase in their Maxillary sinus height (p<0.001). Patients < 6years of age and between 6 and 12 years of age had a significant increase in their maxillary sinus width and depth (p < 0.001). The maxillary sinus width, depth and volume did not increase significantly after the age of 12 years in these patients. CONCLUSION: We demonstrated periods of significant size increase of the maxillary sinuses as determined by different dimensions in children at various ages. The height of the maxillary sinus has steady growth from birth to at least the age of 18 years. The width and depth increase up to 12 years of age.