The analysis of Russian and foreign literature on the definition of somatic sex on the skull is presented. Cranioscopic and craniometric approaches are considered in carrying out craniological studies and existing traditional and modern methods for their implementation. Cranioscopic studies reveal the advantages and disadvantages of W.M. Krogman, G. Acsadi, J. Nemeskeri and V.N. Zvyagina methods. It is shown that the method of V.N. Zvyagina, which includes 40 descriptive diagnostic signs, is the most informative. Its efficiency is 93,5%. The comparative analysis of the craniometric methods for studying the skull according to R. Martin and H. Welcker in the modification of A.P. Bogdanov and a number of English craniologists is presented. The authors point out that the Russian Forensic Center developed a craniological form, which includes 79 different sizes of a skull, by which is possible to determine not only the sex of a skull, but also the approximate age of a person. A comparative assessment of the Russian (V.I. Pashkova) and foreign (E. Giles) craniometric studies is presented. According to V.I. Pashkova using only craniometric techniques allows one to determine the sex of the skull only in 75-80%, and in the complex approach - in 80-93%. The method of E. Giles, based on the study of regression equations, is objective in 83-86%. Thus, studies of the sex determination by skull in an adult should be comprehensive, including both cranioscopic and craniometric techniques.