Leif Segerstam (born March 2, 1944 in Vaasa) is a Finnish conductor and composer.
He studied violin, piano and conducting at the Sibelius Academy in Helsinki and conducting at the Juilliard School in New York with Jean Morel.
He is currently the chief conductor of Helsinki Philharmonic Orchestra. He has held positions with numerous other orchestras, including the Danish National Radio Symphony and the Austrian Radio Symphony, and guest conducted many orchestras throughout the world including the Chicago Symphony, the Los Angeles Philharmonic, the Toronto Symphony and the Brazilian OSESP - the Symphony Orchestra of the State of Sâo Paulo. He is also the professor of conducting at the Sibelius Academy in Helsinki. His students include Susanna Mälkki, Mikk Murdvee, Sasha Mäkilä and Markku Laakso.
He is widely known through his recorded discography, which includes the complete symphonies of Sibelius, Nielsen, and Mahler, as well as many works by contemporary composers such as the Finnish composers Einojuhani Rautavaara and the American composers John Corigliano and Christopher Rouse.