Nikolai Nikolayevich Durnovo (Russian: Никола́й Никола́евич Дурново́; 4 November [O.S. 23 October] 1876 – 27 October 1937) was a Russian linguist. He was executed during the Great Purge.
Durnovo was born to into the Durnovo family. His father was also named Nikolai Nikolayevich Durnovo, while his mother was His mother was a member of the noble House of Saltykov.
Durnovo was a member of the USSR Academy of Sciences (1924) and the Belarusian Academy of Sciences and specialized in Russian language dialectology, the history of Russian and Slavic languages, Russian Language morphology theory of grammar, as well as ancient literature. He created a classification of Russian dialects that served as a base for modern scientific linguistic nomenclature.
During the Great Purge, Durnovo was executed and buried in a mass grave in Sandarmokh.