Background: Sex determination of unknown human remains is very important in forensic medicine, medicolegal cases and forensic anthropology. The identification of sex from adult human skeletal remains is highly reliable if the complete skeleton is available for analysis with 100% precision. The sex discriminant value of the foramen magnum has always attracted attention, although its importance is a controversial subject in the archaeological and anthropological literature. Material and method: Cranial CT Scans were obtained from the local data base of the CT machine and back up compact disc from the CT library of usmanu danfodiyo university teaching hospital (UDUTH) sokoto. Films were viewed on the computer monitor. Measurement was made with Dragon V3.1.1 Philips and Neusoft Medical System Company Limited software, the software provides a meter rule with which measurements were done. Results: A total of 240 subjects were involved in the study. Out of the number, 63(26.25%) were females and 177(73.75%) were males. The ratio male to female was 2.8:1. The age range of the subjects used in this study was 20 to 79 years. The discriminant function analysis was done on all the measurements on the subject used in this study. 67% of all subjects were sexed correctly and 66% and 67% for male and female subjects respectively. Conclusion: This study showed that the most reliable variable for sex prediction is using all the variables at the same time, but the most reliable individual variable for sex prediction for both female and male subjects is using bicondylar distance.