This article discusses the theory naming system of the Kazakh and Bashkir languages. The main sections of Kazakh and Bashkir onomastics are described, the degree of study of its individual sections is analyzed, according to which the course of development of Kazakh and Bashkir onomastics is determined. Although the main sections of onomastics are currently studied in detail, its individual areas still require study and systematization. In this regard, the historical materials that were guided in the study of onomastic space make it possible to identify the linguistic connection of onomastic units, show their connection with the history and culture of the people, as well as to cite the continuity of some phenomena in the formation of historical Kazakh and Bashkir names with a certain period of public life. As a result, it is established that in the basic vocabulary of Kazakh and Bashkir names, along with common Turkic words, other elements are used, and the lack of consistency in modern Kazakh surname writing, and in modern Bashkir, models of writing a person's last name (patronymic) are formed in accordance with the word-forming patterns of the Russian language, are shown on the basis of specific language data.