Cozmin Sime was born in Romania. His repertoire includes Conte Almaviva Le nozze di Figaro, Guglielmo Così fan tutte, Dandini La cenerentola and Belcore L’elisir d’amore. He made his operatic debut at the Romanian National Opera.

He made his international début as Claudio in Donizetti's Emilia di Liverpool for the European Opera Centre and performed Schaunard La Boheme at the Verbier Festival. He sang Barone di Trombonok Il viaggio a Reims under Maestro Alberto Zedda at the Accademia Rossiniana in Pesaro and for Vlaamse Opera.

He was a recent Samling Scholar.