This article is a contribution to the study of the history of the lexis of the Proto- -Slavic language. The etymological analysis of anatomical lexis presented in this article allows us to establish several chronological layers of the lexis: lexemes inherited from the Indo-European proto-language, lexemes from the Baltic and Slavic language communities, lexemes created from Indo-European bases, and lexemes created from Proto-Slavic bases, which are late innovations of the Proto- -Slavic language. Each stage of the history of the Proto-Slavic lexis is documented with appropriate material. In this way this study advances research on the development of Proto-Slavic historical lexicology.