Aim: To determine normal diameters of main and right & left pulmonary arteries, using Computed Tomography in Indian scenario. Materials and Methods: The study, conducted over 6 months, consisted of 100 subjects which qualified our inclusion criteria. Subjects were divided according to Age and Sex. Their respective measurements of MPA and Right & Left PA were taken and analyzed. Results Adults Geriatrics Males Females MPA 22.5 (SD = 2.2)22.9 (SD = 3.2)22.6 (SD = 2.6)22.7 (SD = 2.7) Right PA 16.2 (SD = 2.5)17.7 (SD = 2.7)17.1 (SD = 2.7)16.4 (SD = 2.6) Left PA 16.1 (SD = 2.0)17.8 (SD = 3.1)16.9 (SD = 2.7)16.5 (SD = 2.4) Conclusion: Our findings are an important beginning of a more complete understanding of normal values of mean MPA diameter in Indian Population which differ from references we follow.