The authors of the article focus on the notion of “state language” in an attempt to identify its role linguistically and as it pertains to its legal status. Despite the fact that it is generally understood, the usage of this term is often associated with different notions, resulting in an uncertainty of its meaning. The authors analyze the principles and purposes of establishing a state language, compare the meaning of the term in Russian with similar terms in other lan-guages, including those which were included in the recommendations by UNESCO experts in 1953, and compare the notion with linguistic categories. They conclude that “state language” is a legal concept rather than linguistic or lingvo-didactical. State language is a legal status given to a language in the aim of ensuring the unity of a state (as political nation) and establish-ing a common public communicative and cultural space along with establishing formal rules which require observance, in the spheres, normatively defined, that form the scope of public communication. The scope includes not only interaction with the state, but also encompasses a much greater area of language domains. These aims do not restrict the content of state lan-guage by one functional language style in order to acknowledge its social dialect or genre of language. Functions of organizing a common communicative space for the state language is executed with the linguistic category of standard (literary) language, based on the idea that this part of a national (in linguistic meaning) language is able to provide effective communication between different language communities.