Konstantin IlievIn 1946 Iliev graduated from the Sofia State Academy of Music, where he studied composition with Vladigerov and conducting with Goleminov. He later studied composition with Jaroslav Ridky and Alois Haba at the Prague Conservatory, as well as conducting with Dedecek and Talich. Until 1952 he was Chief Artistic Director of the Ruse State Opera and from 1956 to 1972 the Sofia Opera.
In 1970 he was appointed professor of conducting at the Bulgarian State Conservatory. Together with Lazar Nikolov, Iliev added new dimensions to Bulgarian music in the 1950's and 60's, building on the foundation laid by Pipkov. Having renounced Romantic pathos, they embraced the rational-constructive aesthetics of free tonal thinking and 12- note and aleatory techniques.
Iliev wrote two operas, Boyanskyat maistor (Boyana's Master) after S. Zagorchinov, which was produced at the Sofia National Opera on October 3, 1962. The second was Elenovo zarstvo (The Kingdom of the Deer) with text by Iliev and produced in Ruse in 1976.