Together with the determination of age, ethnicity and stature, the identification of sex from human skeletal remains is an important element in anthropological and forensic assessments. Loth&Henneberg (1996) described a simple morphological feature for sex determination by observing the flexure of the posterior margin of the mandibular ramus, at the level of the occlusal plane and claimed 99% prediction accuracy. To date, reliability of this method in assessing sex in an Egyptian sample has not yet been reported upon. Therefore, the purpose of this study is to evaluate the sex diagnostic power of the method among the adult Egyptians. Orthopantomographic assessment of mandibular posterior ramus flexure as a single sex indicator in 100 adult Egyptians revealed accuracy of 82% for males and 84 % for females and an overall accuracy of 83%. These results differ from those published by Loth&Henneberg (1996). However, they are in agreement with the conclusions reached by several other scholars. It is concluded that, using ramus flexure alone for sex assessment does not provide a high level of confidence and should be used in conjunction with other dimorphic traits.