Gagner, 27, had NHL career highs in points (50), power-play goals (eight) and power-play points (18) in 81 games with the Columbus Blue Jackets last season. His 18 goals tied his previous high from 2011-12 with the Edmonton Oilers.
"There's never really any promises when it comes to ice time, but I see a lot of similarities to the Columbus situation last year," Gagner said. "The opportunity to be a leader and come to a team with a lot of really good young players knocking on the door and some older veterans that feel that didn't feel like they had their best year and there is a lot to prove."
Gagner should help the Canucks power play, which finished 29th (14.1 percent) last season.
"Sam is a hardworking, right-shot center with good speed and skill," Canucks general manager Jim Benning said. "He brings tremendous experience to our team and will set a good example for our younger players."
Selected by Edmonton with the No. 6 pick in the 2007 NHL Draft, Gagner has 402 points (142 goals, 260 assists) in 696 regular-season games with the Blue Jackets, Oilers, Philadelphia Flyers and Arizona Coyotes.
