The article presents the results of the research of Tatar cosmonyms with regard to their origins. It is believed that the lexis of any language is heterogeneous in terms of origins and consists of both aboriginal and borrowed words. The language of the modern Tatars traces its roots to the ancient Turkic language, which was influenced by the Indo-European languages. The research revealed that all those lexical layers are reflected in the cosmonyms of the Tatar language. The smallest group is represented by ancient Turko-Tatar cosmonyms. The next group comprises cosmonyms, borrowed from Arabic. One more group is made up of cosmonyms borrowed from Russian and earlier derived from Latin and Greek. In the 20th century, many Russian cosmonyms (astrotoponyms, for the most part) were translated into Tatar. Lexemes of the first group are used in everyday speech. Meanwhile, Arabic and Latin names of celestial bodies are employed only in scientific and literary Tatar.