Born in Plovdiv, Dimitar Sagaev (1915–2003) graduated from the National Academy of Music in 1940 majoring in Composition under Professor Pancho Vladigerov, Music Theory and Orchestration under Professor Vesselin Stoyanov and Piano under Professor Panka Pelisek. He worked as music teacher at the Plovdiv Male High School (1941-42), bandmaster (1943-46), Head of Art Music Section of Radio Sofia (1946-49), bandmaster of the wind orchestra at the Ministry of Interior (1949-53), music director at the Bulgarian Radio (1946-49) and director of the Music and Opera Theatres Department of the Ministry of Culture (1952-55). In 1948, he joined the staff of the National Academy of Music teaching Symphony Orchestration and Theory of Music. He became full professor and taught generations of composers, conductors and musicologists. He was awarded high state prizes, orders and medals. In 2002 he was given the title Doctor honoris causa by the National Academy of Music.
His wrote in a variety of genres: two operas and two ballets; six oratorios and cantatas; seven symphonies; over 20 instrumental concertos; chamber music, etc. His works are well known abroad. His Concerto for violin and orchestra No.2 was performed by Dina Schneidermann and the Dresden Philharmonic, conducted by Kurt Mazur; his String Quartet No.2 was performed by the famous French ensemble Parenine.