Aim: To find out similarities and differences in the metrical values of different sacral parameters in males and females and to highlight the best parameter that could be used to study sexual dimorphism of sacrum. Materials and methods: 140 (83 male and 57 female) adult human sacra were collected from Department of Anatomy, Government Medical College, Aurangabad, Maharashtra. The measurements included ventral straight length and maximum breath of sacrum, sacral index, maximum transverse and antero-posterior diameter and index of body of first sacral vertebra. Demarking points for these parameters were used for identification of sex of sacrum. Results: The average values of sacrum for ventral straight length was found to be 104.7__ampersandsignplusmn;5.94 mm in male and 92.6__ampersandsignplusmn;6.1 mm in female, maximum breadth was 102.93__ampersandsignplusmn;4.83 mm in male and 104.77__ampersandsignplusmn;6.48 mm in female and sacral index was 98.44__ampersandsignplusmn;4.69 mm in male and 113.23__ampersandsignplusmn;5.61 mm in female. The average values of first sacral vertebra for transverse diameter was 48.48__ampersandsignplusmn;4.21 mm in male and 40.75__ampersandsignplusmn;3.51 mm in female, antero-posterior diameter was 29.12__ampersandsignplusmn;2.47 mm in male and 26.93__ampersandsignplusmn;2 mm in female and index was 60.28__ampersandsignplusmn;4.96 mm in male and 66.36__ampersandsignplusmn;5.04 mm in female. Conclusion: Sacral index was found to be the best parameter for sex determination of sacrum amongst the parameter studied. Using sacral index alone 27.71% of bones in males and 57.9% of bones in females could be identified. However not a single parameter could identify 100% of the bones.