Born in Tegernsee, Germany, Quirin Willert took up accordion and piano at the age of six. This was followed by the trombone at the age of eleven years, with which he gained early orchestral experience in the Bavarian State Youth Orchestra. He completed his studies at the universities of music in Munich and Frankfurt am Main under Wolfram Arndt and Oliver Siefert. In 1988/1999 he played as intern in the Augsburg Philharmonic before continuing his career in the Tyrol Symphony Orchestra in Innsbruck. Back in Munich, he assumed the position of trombonist for all chairs in the orchestra of Staatstheater am Gärtnerplatz, of which he was a member for 14 years. He joined the Munich Philharmonic in March 2015.