Olga Peretyatko (Russian: Ольга Перетятько; Leningrad, now Saint Peterburg, 21 May 1980) is a Russian operatic soprano. As a child Peretyatko sang in the children's choir of the Mariinsky Theatre. As a student of the Hamburg Opera Studio she received the second prize at Operalia Competition (2007), an event sponsored by tenor Plácido Domingo.
Her repertory includes operas from Handel and Mozart to Richard Wagner and Richard Strauss. A participant at the Accademia Rossiniana in Pesaro, she has regularly sung at the Rossini Opera Festival: Corinna and Contessa di Folleville (Il viaggio a Reims, 2006), Desdemona (Otello, 2007), Giulia (La scala di seta, 2009), Aldamira (Sigismondo, 2010), and the title role in Matilde di Shabran (2012). In 2013 she sang during the Mozartwoche in Salzburg.
In 2014, she made her Metropolitan Opera debut as Elvira in Bellini's I puritani.
She is married to the conductor Michele Mariotti, who led the Matilde di Shabran performances in Pesaro.