Brad Richardson had a goal and an assist, and Peter Budaj stopped 23 shots in a game that Colorado only led by one goal until Tyler Arnason scored with 7:36 left in the third period to give the Avalanche a 3-1 lead.
Brett McLean, Ken Klee, Mark Rycroft and Jeff Finger also scored for Colorado, which started a five-game road trip and won its second straight. Finger's goal was his first in the NHL.
Budaj said Richardson's goal, the Avalanche's first, was the key. It tied it 1-all early in the first period.
"I think for our team the biggest goal was the first," said Budaj, who posted his 20th win.
Richardson was credited with the goal following an unusual, delayed video review. The teams continued to skate for 1 minute, 54 seconds after Richardson slid and knocked the puck into the net at 7:43 because no whistle sounded and the puck bounded back into play.
"A little bit of luck, but never bad to have on your side," Richardson said. "I thought I got hooked a bit, but you know, whatever. I just went down and it turned out nice for me and I'll take it."
Tuomo Ruutu scored for Chicago, which lost for the fifth time in six games. The Blackhawks are 1-5-2 in their past eight.
With Colorado ahead 2-1 in the second, a possible goal by Chicago' s Jason Williams at 7:50 was disallowed after a video review.
"It's kind of funny," Budaj said. "After every goal we were kind of waiting for a decision."
With the score still 2-1 in the first minute of the third, Chicago's Patrick Sharp rattled a drive off the post on a breakaway.
"That was a good shot," Budaj said. "I'm glad I got a little lucky there."
Chicago's Nikolai Khabibulin stopped 26 shots.
"We got two bad breaks," Chicago coach Denis Savard said. "We played right with them until they got that third goal.
"It was one of those games where, if the bounces go our way, it could have been a different score," he added. "The score didn't indicate the kind of game we had."
Blackhawks leading scorer Martin Havlat returned to the lineup after missing Tuesday's game against Detroit with the flu. Savard said Havlat lost nearly 10 pounds in a few days.
"He played pretty hard they, but he couldn't go at the end," Savard said. "He's pretty worn out now, no question. Hopefully he can get something in his stomach now."
Havlat, the Blackhawks' top offensive player, lacked his usual energy Thursday. However, he was credited with an assist on Ruutu's goal.
After Budaj stopped Adrian Aucoin's drive from the left point, Havlat hacked at the rebound before Ruutu put it in for a 1-0 Chicago lead.
Richardson's goal at 7:43 of the first tied it 1-all.
After being hit by Chicago defenseman Brent Seabrook, Richardson slid into the net - and Khabibulin - and knocked the puck into the net with his knee.
Khabibulin kicked the puck out with his right pad and play continued without a whistle for almost two minutes. Once action stopped, Richardson's play was reviewed by the NHL's Toronto office.
An overhead camera angle showed the puck had crossed the goal line by about a foot. The goal was awarded and the clock was rolled back to the 7:43 mark.
McLean made it 2-1 with 9:16 left in the first, converting a rebound of Milan Hejduk's shot.
Williams' goal at 7:50 of the second was disallowed following a video review. It didn't appear the puck crossed the goal line.
On the play, Colorado defenseman John-Michael Liles covered the puck in the crease. However, neither of the referees, Mike Hasenfranz or Dennis LaRue, awarded Chicago a penalty shot.
Arnason made it 3-1 with 7:36 left in the third. From the edge of the crease, he redirected Richardson's centering pass.
Klee made it 4-1 with an empty-net goal with 1:52 left. With Khabibulin back in goal, Rycroft and Finger connected in the final 1:26 to complete the scoring.
Colorado RW Scott Parker played his first game since rejoining the Avalanche in a trade from San Jose on Tuesday. Parker spent his first four seasons with Colorado. ... Avalanche D Karlis Skrastins missed his third game with a knee injury after playing in 495 straight contests to set an NHL record for a defenseman. RW Marek Svatos sat out with a groin injury. ... Chicago RW Nikita Alexeev played his first game with the Blackhawks after being acquired from Tampa Bay on Tuesday and saw both even-strength and power-play duty. ... Chicago RW Rene Bourque missed the game with the flu.