Ingo Metzmacher (born 10 November 1957, Hanover) is a German conductor. He is the son of the cellist Rudolf Metzmacher and the research biologist Lore Schoen. His musical education in piano, music theory and conducting was in Hanover, Salzburg and Cologne. He later joined the Ensemble Modern in 1981 as its pianist, and became the orchestra's conductor in 1985.
In 1994, Metzmacher conducted the premiere of the revised version of Hans Werner Henze's Symphony No. 6. In 1997, he conducted the world premiere of Henze's Symphony No. 9 at the composer's request. From 1997 to 2005, he served as General Music Director of City of Hamburg, which covered the Hamburg State Opera and its Philharmonic Orchestra. He left his post in Hamburg after disputes with the city over funding.
In 2005, he became chief conductor of De Nederlandse Opera. In February 2007, De Nederlandse Opera announced that Metzmacher would step down from his post as DNO's Chief Conductor in 2008. From 2007-2010 he was the Chief Conductor and Artistic Director of the Deutsches Symphonie-Orchester Berlin (DSO-Berlin). His original contract with the DSO-Berlin was through 2011. However, after reports of disputes over financing and a threatened reduction in the size of the orchestra, in March 2009, Metzmacher announced his early resignation from the DSO-Berlin principal conductorship as of the summer of 2010. His final concerts as the orchestra's principal conductor were in June 2010 in Berlin and in August 2010 at The Proms.