After completing studies at the State Tchaikovsky Conservatoire, specialising in music theory, he studied composition with Jörg Herchet at the Hochschule für Musik in Dresden and with Friedrich Goldmann at the Universität der Künste in Berlin, where he also graduated in music theory and pedagogy with Hartmut Fladt.

Since 1994 his music has been performed at leading international New Music festivals, including the Donaueschingen Festival, Wien Modern, Éclat, Gaudeamus Music Week, Berliner Festwochen and the ISCM World New Music Days. He has received commissions from, among others, Klangforum Wien, SWR, Deutschlandradio, Berlin Konzerthaus, Deutsche Staatsoper Unter den Linden and the Norwegian Ministry of Culture commissioned work for him.

In 2006 Newski won 1st Prize at the Stuttgart composition competition for his piece “Fluss”. In addition, he was awarded various scholarships, such as Villa Massimo/Casa Baldi, Villa Serpentara, Villa Aurora, Cité Internationale des Arts Paris and the Akademie der Künste Berlin. In September 2012 his opera “Franziskus” premiered at the Bolschoi Theater. In 2013 his portrait-CD “Alles” produced by the German Music Council was issued on the Wergo label. During 2011 and 2012 Sergej Newski worked as music curator and lecturer for “Platform”, a series of events organized by the Center for Contempoary Art Vinzawod in Moscow.