Background: Aim of the study is to determine sex of sacrum using different parameters like curved length, vertical length, anteroposterior diameter and transverse diameter of first sacral vertebra, width of sacrum, length of ala and extent of sacral hiatus. Materials & Methods: The intact sacra of 110 adult human of known sex obtained from government medical college Aurangabad. The various parameters like length, width, curved length, anteroposterior and transverse diameter of first sacral vertebra were measured by using thread, sliding caliper and ruler. Several indices like sacral index, curvature index corporobasal index and alar index were calculated. Results: Demarking points were evolved and none of the parameters appeared to be promising in identifying sex, except transverse diameter of first sacral vertebra and length of sacrum which is useful in study of medico-legal cases. Various indices were calculated using standard formula for each, the mean and standard deviation for each index was calculated along with demarcating points which determine sex with about 100 percent accuracy.

Key Words: Sex Determination, Sacrum