Byron Fidetzis was born in Thessaloniki, where he studied the cello at the State Conservatory, continuing on a Hellenic Foundation scholarship at the Vienna Musikhochschule with Vladimir Orloff, André Navarra and S. Benes, and attending conducting classes under Hans Swarowsky.
He has collaborated as a soloist and conductor with all the Greek and many foreign orchestras in concerts and festivals throughout Greece and abroad. From 1985 to 1992 he was permanent conductor of the orchestra of the Greek National Opera House, and from September 1990 to 1992 chief conductor of the Ekaterinburg State Philharmonic Orchestra of the former Soviet Union. Since 1992 he has been Guest Conductor of the Russian State Capella Orchestra in Moscow (the official orchestra of the Ministry of Culture in the former Soviet Union), and was also Honorary Guest Conductor of the Symphony Orchestra of Pasardjik in Bulgaria until 1999, serving from 1999 to 2001 as Artistic Director to the same orchestra. From 2000 to 2005 he was Chief Conductor of the Symphony Orchestra of the Municipality of Thessaloniki, and since 1987 has been permanent conductor of the Athens State Orchestra and from 2004 also its Artistic Director.