Viktor Yevseyevich Suslin (Russian: Ви́ктор Евсе́евич Су́слин; 13 June 1942, Miass, Ural, Russia – 10 July 2012, Hamburg, Germany) was a Russian composer. An associate of Sofia Gubaidulina's, together with her and Vyacheslav Artyomov he formed the improvisatory ensemble 'Astraea' in 1975. He emigrated to Germany in 1981.
He worked as an editor at the publishing house Muzyka in Moscow (1966–1980). Suslin became a member of the Union of Soviet Composers in 1967. In 1969 his piano sonata was given an award at the Young Composers Competition. In 1971 his music was performed outside of Russia for the first time at the Festival de Royan, France.
Suslin taught instrumentation at the Moscow Conservatory (1972–1975). In 1975 he founded the ‘Astraea’ improvisation ensemble together with Vyacheslav Artyomov and Sofia Gubaidulina.
In November 1979 after several performances of his works in Paris, Cologne and Venice, Suslin was publicly denounced and blacklisted as one of the "Khrennikov's Seven" at the Sixth Congress of the Union of Soviet Composers for unapproved participation in some festivals of Soviet music in the West.
Suslin was good friends with Galina Ustvolskaya toward the end of her life, exchanging letters with her and facilitating an interview with Thea Derks. Sikorski ostensibly began to publish Ustvolskaya's works while Suslin was an editor there.