Markus Merk (born 15 March 1962) is a former top-level German football referee. He is a six-time winner of the German Referee of the Year Award and the record holder in games refereed in the Bundesliga. In 2005, Merk was awarded the German Bundesverdienstkreuz (Federal Cross of Merit) in recognition of his service to football and his charity work in India. He ended his career by refereeing the match between Bayern Munich and Hertha BSC Berlin on the last day of the 2007–08 Bundesliga season on 17 May 2008.
He was ranked the best referee by the International Federation of Football History & Statistics in 2004, 2005 and 2008.