Tim Schaller scored for the Bruins (35-13-8), who lost in regulation for the third time in 27 games (20-3-4). Boston remains second in the Atlantic Division and Eastern Conference, three points behind the Tampa Bay Lightning.
"Their goaltender was very good," Bruins coach Bruce Cassidy said. "This had the makings, it could have been one of those 6-5 jobs. I thought he was really good, we hit some posts, but at our end, it's crept into our game, we are loose. We've got to nip it in the bud."
Bruins goalie Tuukka Rask was pulled after giving up four goals on eight shots in the first period, but three of the goals came on rebounds or broken plays in front of him. Anton Khudobin stopped 13 of 15 shots in relief.
"Those things happen but you have to deserve your bounces and [I] definitely wasn't at my sharpest," said Rask, who was 20-1-2 in his past 24 games. "I just have to look in the mirror and be better, it doesn't matter what happens in front of me."
Eriksson gave the Canucks a 1-0 lead at 2:00 of the first period on a rebound, and Sedin (10:54) and Horvat (11:50) scored 56 seconds apart to make it 3-0.