Russian grammar employs an Indo-European inflexional structure, with considerable adaptation.

Russian has a highly inflectional morphology, particularly in nominals (nouns, pronouns, adjectives and numerals). Russian literary syntax is a combination of a Church Slavonic heritage, a variety of loaned and adopted constructs, and a standardized vernacular foundation.

The spoken language has been influenced by the literary one, with some additional characteristic forms. Russian dialects show various non-standard grammatical features, some of which are archaisms or descendants of old forms discarded by the literary language.

Various terms are used to describe Russian grammar with the meaning they have in standard Russian discussions of historical grammar, as opposed to the meaning they have in descriptions of the English language; in particular, aorist, imperfect, etc., are considered verbal tenses, rather than aspects, because ancient examples of them are attested for both perfective and imperfective verbs. Russian also places the accusative case between the dative and the instrumental, and in the tables below, the accusative case appears between the nominative and genitive cases.