As a junior, Pettersson made three appearances with the Swedish under-20 team. He was a member of the under-18 squad that won the bronze medal at the 2005 IIHF World U18 Championships, and helped guide the Swedes to fifth and fourth place finishes in the 2006 and 2007 World Junior Hockey Championships. Pettersson made his first senior world championship appearance with the Swedish national team in 2010. He had two points in seven games for the bronze medal-winning Swedes.