Forensic sex determination is crucial for human identification, and the mandible, the largest strongest and movable part of the skull, is often recovered intact and being a practical element to analyze sexual dimorphism in fragmented bones. Objectives: The present study was designed to compare mandibular measurements on both sides to determine sex through 3-dimensional CT skull images of Egyptian individuals. Subjects and Methods: The study analyzed computed tomography (CT) radiographs from 36 male and 36 female cases at Zagazig University, calculating mandibular linear measurements and angles, and comparing them using statistical analysis. Results: The study results showed statistically highly significant differences between males and females in all the seven linear measurements taken from the mandible (P below 0.01), whereas the differences in the three angles calculated from the seven linear measurements were not statistically significant (p above 0.05). The left and right coronoid to gonion linear measurements showed the greatest discriminative power compared to other parameters. An equation for sex prediction from each of these 2 parameters was also developed to be applied in cases when only half of the mandible is available. Conclusion: Mandibular measurements can be used as a useful tool for sex determination. The mean values of right and left Condylar Ramus height and distance from the superior margin of the mental foramen to the mandible (SM-IB) inferior margin were the correct predictors of both genders. Keywords: Forensics, Sex determination, CT, Mandible