Reinhard Mahlberg was born in Mönchengladbach. He studied drama at the Berlin University of the Arts, before working at the Constance City Theatre and the Hanover State Theatre. From 2002 to 2018, he was an ensemble member at Mannheim National Theatre. Theatre aside, Mahlberg appears on television and works for various radio stations. He has been a permanent ensemble member at Schauspiel Stuttgart since the 2018/19 season.