Hansen advanced to the under-20 level, playing in Division I of the 2004 World Junior Championships, held in Berlin. He registered an assist in three games as Denmark finished second in their group to Germany, missing out on a promotion to the main tournament for the following year. He returned to the under-18 team for a third time later that year. Competing in the main tournament, Denmark finished in seventh place. Hansen scored seven points in six games, third in team-scoring. At the 2005 World Junior Championships, Hansen helped Denmark to a third-place finish in their five-team Division I group. He led his team with four goals and added an assist for five points over five games.