Claude Lelong studied the viola with Prof. Maitre Pascal in the Conservatoire National Superieur de Musique in Paris, France.

His career includes: First Prize First Named and Award of the Foundation of St. Paul given to the best First Prize of the year in 1958. Laureate of the International Competition of Geneva (Viola) in 1960.

In 1963, he started soloist career, performing the works like Schwanendreher (Hindemith), Concerto for Viola and Orchestra(Stamitz), with the Chamber Orchestra of Berlin and in other formations in Berlin, Bruxelles, Lille, Zurich, Lausanne, Hamburg, Warsaw, Amsterdam, London, etc.

In 1966, Claude Lelong acquired by competition the position of Principal Viola Soloist in the German Opera of Berlin (Chief Conductor Lorin Maazel). For 20 years of 1966-1986, he had numerous concerts as soloist with "Gruppe Neue Musik Berlin" in Europe(France, Switzerland, the Netherlands, Belgium, England) and in USA.

Claude Lelong won the First Prize of International Competition of Chamber Music in Colmar (String Trio) in 1972. The City of Berlin bestows him the title of "Berlin Chamber Virtuoso" in 1979.

In 1981-1990 he had numerous concerts as soloist with the orchestra of the German Opera of Berlin.
In 1983, the French Government honoured him with the title "Chevalier de Ordre du Merite" in acknowledgment of his artistic achievements in the course of his career.
In 1985 he founded "Ensemble Debussy", having many concerts in Europe.