2009-10: Dillon Fournier garnered a lot of attention for his play with the Lac Saint-Louis Lions midget AAA team as the Lions came up just short of the Telus Cup – falling to College Antoine-Girouard in the Quebec finals. In 39 regular season games he had 12 assists with 24 penalty minutes and he recorded 3 assists with 40 penalty minutes in 21 playoff games. Fournier was the first overall selection in the 2010 Quebec Major Junior Hockey League's Entry Draft – being selected by Lewiston.
2010-11: Fournier skated in 60 games for Lewiston in his first QMJHL season and represented Quebec in the 2011 U17 World Hockey Challenge. Joining his older brother Stefan, a forward who scored 20 goals in his second season with the the MAINEiacs, Dillon Fournier scored 3 goals with 11 assists and was plus-nine with 38 points. Lewiston, which finished second in the East Division, advanced to the playoff semifinals. In 11 playoff games, Dillon Fournier had 2 assists and was plus-one with 15 penalty minutes. In six games for Team Quebec at the WHC he had 1 goal with 2 assists and 8 penalty minutes.
2011-12: Fournier was selected by Rouyn-Noranda with the first pick in the Dispersal Draft after Lewiston folded. He saw a lot of ice time on a Huskies team that was one of the QMJHL's weaker clubs. Despite missing time with a shoulder injury, Fournier was the second-leading scorer amongst Huskies defensemen, finishing with 9 goals and 29 assists in 52 games. He was minus-eight with 59 penalty minutes. After finishing last in the West Division, the Huskies were swept by Shawinigan in a four-game playoff series. Fournier did not play in any of those games. Ranked 136th amongst North American skaters in Central Scouting's final rankings prior to the 2012 NHL Draft he was selected by Chicago in the second round (48th overall).
A puck-mover with great skating ability, Fournier's development may have been slowed by injuries in his draft year, but he is in a good situation with his junior team. They heavily rely on his presence on the blue line and thus he gets opportunities in all situations. This gives him the opportunity to improve all aspects of his play. Still honing his play at both ends of the ice, Fournier needs to get stronger but he's developing into a talented two-way defender.
Fournier is expected to be healthy for the start of the 2012-13 season and play on the top pairing for Rouyn-Noranda in the Quebec league, skating in all situations with the goal of improving his overall game.