Boris Blacher (January 6 (O.S.) / January 19 (N.S.), 1903 - January 30, 1975) was a German composer.
Born in the Manchurian town of Niuzhuang (also spelt Newchwang; now called Yingkou), Blacher spent his first years in China and in the Asian parts of Russia, and in 1919, he eventually came to live in Harbin. 1922, after finishing school, he went to Berlin where he began to study architecture and mathematics. Two years later, he turned to music and studied composition with Friedrich Ernst Koch.
He later became director of the Music Academy of Berlin, and is today regarded as one of the most influential music figures of his time. His students include Aribert Reimann, Isang Yun, and Maki Ishii.