Sergei Mikhailovich Tretyakov (Russian: Серге́й Миха́йлович Третьяко́в; 20 June 1892, Goldingen, Courland Governorate (modern day Kuldīga, Latvia) – September 10, 1937, Moscow) was a Russian constructivist writer, playwright and special correspondent for Pravda. He graduated 1916 from the department of law at Moscow University. He began to publish in 1913 and just before the Russian Revolution he became associated with the ego-futurists. Soon after the publication of Iron Pause, he became heavily involved in the Siberian futurist movement known as Creation along with artists such as Nikolay Aseyev and David Burlyuk. Perhaps his most famous play at the time was Roar China!, which attacked what he perceived as Western imperialism.

In 1924 Sergei Tretyakov made a lengthy visit to China where he taught Russian literature and collected materials for some of his later publications. Tretyakov also wrote the controversial "I Want a Baby" ("I Want a Child") (1926), which has seen recent performances in Europe and America. He was a key contributor to the constructivist journal LEF, (1923–1925) and co-edited the Novyi LEF (New LEF) magazine (1927–1928). Between 1930 and 1931 he travelled in Germany, Denmark, and Austria. Before he fell foul of the authorities he translated and popularised other European writers such as Bertolt Brecht. Brecht was also familiar with Tretyakov's literary work. Tretyakov contributed song lyrics to the film Pesn' o geroyakh (Song of Heroes) by Joris Ivens set in music by Hanns Eisler.

Tretyakov was arrested by Joseph Stalin's NKVD on July 27, 1937 and charged with espionage. He was eventually executed later that year as part of the Soviet Union's Great Purge. However, in the introduction to the English publication of 'I Want a Baby', Robert Leach says it seems that in a last act of defiance he threw himself to his death down the stairwell at Butyrka prison. During the 1960s, Tretyakov was posthumously rehabilitated along with many other victims of Stalin's purge.