Following his ice hockey career Mirko Holbus became a renowned businessman in both Yugoslavia and Serbia. Holbus spent his entire playing career with Partizan Beograd and was later appointed as the President of the club. During the 1960s he also represented the Yugoslav national ice hockey team, playing in eight matches at the 1964 Innsbruck Olympics. After his retirement from the sport in 1968 he then worked in the crude oil sector, selling products around the globe from various bases in Europe. Holbus worked in the oil industry until 2002 when he became a business owner of a debt collection company in Serbia. Since his death in 2015 the Mirko Holbus Memorial Tournament has been played, which is contested between the best youth teams in the country.