Nikolai Ivanovich Ashmarin () (, Yadrin, Kazan Governorate – August 26, 1933, Kazan) was a Russian scholar who specialized in the study of Chuvash language, culture, and history. His magnum opus is "The Dictionary of Chuvash Language", published in 17 parts between 1928 and 1958. He was also a Doctor of Turkology (1925). After graduating from the Lazarev Institute in 1896, Ashmarin taught at the schools and universities of Kazan (with short spells in Simbirsk and Baku). He published a valuable collection of Chuvash songs in 1900. He was elected a corresponding member of the Academy of Sciences of the USSR in 1929.