As a passionate musician, Henri Demarquette performs with top French and international orchestras across the globe: Orchestre National de France and Orchestre National de Bordeaux Aquitaine, Orchestre de chambre de Paris, London and Ural philharmonic orchestras, NDR Elphilharmonie, Tokyo and St. Petersburg Symphony orchestras, Sinfonia Varsovia, Neue Philharmonie Westfalen, to name but a few. His piano partners include Boris Berezovsky, Michel Dalberto, Jean-Bernard Pommier, Fabrizio Chiovetta, Vanessa Benelli Mosell and Jean-Frédéric Neuburger.
 
Henri Demarquette is also very involved in contemporary music and original projects, such as his own ​‘Vocello’ (ensemble for cello and a capella choir). This innovative creation puts in perspective works from the Renaissance with contemporary pieces. To this point ​‘Vocello’ premiered 12 works from Eric Montalbetti, Justė Janulytė, Thierry Escaich, Baptiste Trotignon, Philippe Hersant, and Éric Tanguy amongst others.
 
Henri Demarquette was awarded the Prix de la Fondation Simone et Cino del Duca in 2005.

He plays ​‘le Valslin’ cello, crafted by Stradivarius in 1725 and lent by LVMH/Moët Hennessy Louis Vuitton.