Couturier's international hockey career began with back-to-back appearances for Canada Atlantic at the World U-17 Hockey Challenge in 2008 and 2009. His team finished eighth and ninth in the tournaments, respectively. In 2009, he also participated in the Ivan Hlinka Memorial Tournament, helping to capture a gold medal for Canada. In 2011, he became the only player under the age of 18 to be named to Team Canada at the World Junior Ice Hockey Championships. Although he had a solid performance, scoring three points in seven games, Couturier was largely overshadowed in the tournament by fellow prospects Brayden Schenn and Ryan Johansen. Canada won silver at the WJC, losing to Russia in the finals.