Fantuz spent the majority of his professional career with the Saskatchewan Roughriders and the Hamilton Tiger-Cats of the Canadian Football League (CFL).

Andy Fantuz attended the University of Western Ontario from 2002 to 2005, where he established himself as one of the best receivers in Canadian Interuniversity Sport history.

[1] Fantuz won the Hec Crighton Trophy as the top player in the CIS in 2005, finishing with 44 catches for 825 yards to become only the fifth receiver to win the award and first since Calgary's Don Blair in 1995.

Quarterback Kerry Joseph was rushing towards the endzone deep in BC territory when he was tackled from behind and fumbled the ball forward.

[5] The 2007 season was presumably a promising one for Fantuz as the media and coaching staff alike were expecting big things from the sophomore receiver.

However, the sophomore slump took its toll on Fantuz as numerous dropped balls at critical junctures led to his demotion from the starting line-up in week 5 by head coach Kent Austin.

He continued his strong play with a 7 catch – 142 yard performance against the Montreal Alouettes, filling in for Matt Dominguez who was injured in the Banjo Bowl.

However, in a game against Toronto, Fantuz suffered a broken fibula, the smaller, non-weight bearing bone in his left leg while being tackled in the fourth quarter of the July 27, 2008, 28–22 victory.

He returned for the Banjo Bowl against the Winnipeg Blue Bombers and caught two passes for 64 yards and a touchdown, which was thrown by fellow receiver, Jason Armstead, on a gadget play.

He had an outstanding outing in the overtime game against the Calgary Stampeders, contributing 10 catches for a season-high 149 yards and a game-tying touchdown.

Fantuz finished the season with a career-high 67 receptions for 882 yards and three touchdowns and was tied with Chris Getzlaf for the team lead in two-point conversions with two.

In the 2009 West Final, he had a game-high five receptions for 89 yards and one touchdown, which was part of the 27–17 win over the Stampeders that featured all Roughrider scoring by Canadian players.

On October 15, 2009, Fantuz stated that he had verbally agreed to a two-year contract extension with the Roughriders, but would examine his NFL options before February 15, 2009.

During the Summer of 2010, as part of their "100 years of The Roughriders" promotional campaign, Federated Co-op Ltd. released a breakfast cereal under the name "Fantuz Flakes".