The 27-year-old, sixth in the 10km sprint at the Winter Olympics in 2010, shot a perfect ten in the same event in Sweden to romp to his first-ever World Cup win in 25:10.4.
And, not only is Leguellec the first Canadian male to ever win a World Cup race, his success is the biggest for the nation in the sport since Myriam Bedard took double Olympic gold at Lillehammer 1994.
Leguellec was one of only two in the top 10 to shoot perfectly however his skiing was just as good as he won by a margin of 18.1 seconds over Alexis Boeuf of France.
Boeuf missed just one of his 10 targets but showed a better turn of pace than Christoph Sumann to beat the Austrian into second by over six seconds.
Reigning World Cup champion Martin Fourcade, who won the 20km individual earlier in the week, missed three targets to finish 10th over 40 seconds behind Leguellec.