In 43 games over three seasons with the Winnipeg Blue Bombers, Bowman registered 153 defensive tackles, 29 special teams tackles, nine quarterback sacks, two interceptions and two fumble recoveries.
Last season, the six-foot-three, 228-pound Boston College product made a career-high 52 tackles and two sacks.
The 26-year-old recently underwent knee surgery, but Kent Austin, the Tiger-Cats' vice-president of football operations, general manager and head coach, says the team is confident Bowman will be a valuable asset to the team.
"Marcellus is an extremely talented player and a game-changer on defence," Austin said in a statement. "We're well aware that he recently underwent a medical procedure but feel comfortable making this signing after consulting with our doctors. Our medical staff will work closely with Marcellus to ensure he returns to the field at 100 per cent as soon as possible. We're very excited to have Marcellus on board."