Sergei Aleksandrovich Yermolinsky (Russian: Сергей Александрович Ермолинский; 14 December 1900, Vilnius – 18 February 1984, Moscow) was a Soviet screenwriter and dramatist.
He studied at the Institute of Oriental Studies and in 1925 graduated from the Literature Faculty of Social Sciences at Moscow State University, going on to work on the newspapers Pravda and Komsomolskaya Pravda and in 1925 to collaborate with the film director Yuli Raizman.
He became friends with Mikhail Bulgakov, whose participation in the Commission of the Union of Writers was partly what led to Yermolinsky's arrest in late 1940 - the order was signed by Pyotr Pavlenko.
Nikolay Cherkasov and Sergei Eisenstein successfully petitioned the Kazakhstan People's Commissar of the NKVD for his release in 1943 and took him on as a screenwriter in Almaty.
He moved to Moscow secretly due to his exile status in 1946-1947 and then openly in 1949, before being rehabilitated in 1956 after the death of Stalin.