Introduction: The dimensions of the foramen magnum are clinically important because vital structures passing through it may endure compression such as in cases of foramen magnum herniation, foramen magnum meningiomas and foramen magnum achondroplasia.The current studyamined to measure the anteroposterior diameter, transverse diameter, area and index of foramen magnum in adult Indian skulls. Materials and Method: The present study was carried out on foramen magnum of 55 dry adult skulls of known sex (36 male skulls and 19 female skulls) from bone library of department of Anatomy, GMC Aurangabad. The anteroposterior diameter and transverse diameter of foramen magnum were measured using digital vernier caliper. Area and index of foramen magnum were calculated using both diameters. Results: The mean value of anteroposterior diameter in males was 34.99 mm whereas that in females was 33.75mm.Also, The mean value of transverse diameter in males was 28.53 mm whereas that in females was 27.41mm.The mean area of foramen magnum was 765 Sq.mm.in males and 728 Sq mm. in females. The index of foramen magnum was 81.79 in males and 81.39 in females. Conclusion: The anteroposterior and transverse diameters, area and index of foramen magnum of male skulls were greater than females. This study of the morphometric analysis of foramen magnum will be helpful to anatomists, anaesthetists, radiologists and neurosurgeons and anthropologists.

Keywords: Foramen Magnum; Skulls; Morphometric analysis.