Context: Sacrum shows sexual diamorphism and hence functionally influences the pelvis. Sexual diamorphism is also influenced by the interaction between the environmental and genetic factors. Based on various sacral indices gender discrimination of the skeletal material can be done to establish the identity of the individual. Aims: To study various sacral indices in sexual dimorphism in the region of Gujarat and compare it with other studies. Settings and Design: Various sacral dimensions of dry scara were measured with the help of vernier calliper and flexible tape. Various sacral indices were calculated and statistically analysed. Methods and Material: The study was conducted on 110 adult sacra dry bone of known sex (62male and 48 female) obtained from the department Anatomy, GMC Surat, SMIMER and BJMC Ahmadabad. Statistical analysis used: The observations were tabulated for quantitative variable (Mean+/- 3SD). Two independent sample t test was applied to check group mean differences. The minimum in male range (A to B) and maximum in female range (C to D) were chosen as demarking points respectively for females and males. Results: In the present study the P value of various sacral indices was found to be less than 0.005 and thus highly significant. Conclusions: Based on various sacral indices and demarking points the sexual diamorphism of sacrum can be established with increased accuracy. The metric parameters are significantly different for different population groups.