"This is a difficult decision for me, but it will benefit my health and my whole family," said the 31-year-old linebacker.
"This gives me an opportunity to be a full-time father and will allow me to spend some quality time with my family."
A native of British Columbia, Reid went to school at Boise State in Idaho. He started his CFL career in 1995 with the Ottawa Rough Riders. In 1996, the Alouettes selected him in the expansion draft.
Stefen Reid is retiring after eight CFL seasons. (CP Photo)
"Although we are extremely sad to see Stefen go, we wish him nothing but success, " said general manager Jim Popp.
"Stefen was a major factor in the rebirth of the Alouettes in Montreal. His passion for the sport and his leadership were contagious and we know he has a bright future in front of him. "
In 18 games last season, Reid recorded 65 tackles, six sacks and two interceptions. He wasa also a key contributor on an Als team that won the Grey Cup last season.
Reid finishes his career with 447 tackles, 19 sacks, seven interceptions and a touchdown in 130 career games.
