Hedman played for Sweden at the 2008 World Junior Championships, where he helped the team to a silver medal, losing to Canada 3–2 in the final, and was selected to the tournament All-Star Team. He later became one of the youngest players to play for Sweden's men's team when he made his debut at age 17 in an exhibition game against Norway. Hedman would once again play for Sweden's junior team at the 2009 World Junior Championships in Ottawa, where he met Canada for the second consecutive year in the gold-medal game, earning another silver medal in a 5–1 loss.