Count Sergei Lvovich Tolstoy (Russian: Сергей Львович Толстой; 10 July 1863, Yasnaya Polyana – 23 December 1947, Moscow) was a composer and ethnomusicologist who was among the first Europeans to make an in-depth study of the music of India.

[1] Over the next ten years, he came to the defense of many Tolstoyans who were being suppressed for anti-government activities; notably Leopold Sulerzhitsky.

From 1898 to 1899, he helped to organize the Doukhobor community for resettlement in Western Canada and accompanied them to Lawlor Island in Nova Scotia.

[1] During this time, he also composed, setting the words of several poets to music; including Pushkin, Fofanov, Fet and Tyutchev.

[1] After the October Revolution, he worked in the music department of the People's Commissariat and participated in expeditions to gather folklore.