The Jesenice, Slovenia native has championed Slovenian hockey into the international eye, representing his home country on various international competitions, including, six IIHF Men's World Championships (2005, 2006, 2007 (Division 1), 2008, 2015, 2019 (Division 1A - captain)), three IIHF World Junior Championships (2004 (Division 1), 2005 (Division 1), 2006 (Division 1)) and three IIHF Under-18 Men's World Championships (2003 (Division 1), 2004 (Division 1), 2005 (Division 1)). Kopitar also captained Team Europe to the championship game against Canada at the 2017 World Cup of Hockey. In 64 international appearances with Slovenia, Kopitar has posted 82 points (41-41=82) with 34 PIM and a plus-nine rating.