Ales Hemsky, Jordan Eberle, Shawn Horcoff and Nail Yakupov, into an empty net, scored on the man advantage for the Oilers.
Taylor Hall and Sam Gagner each picked up two assists for Edmonton, which got a strong start to a game after falling behind in each of its four previous outings.
P.A. Parenteau scored for the Avalanche, who have lost two in a row to start a four-game road trip.
Edmonton opened the scoring at 15:23 of the first. Hemsky swooped in and swatted a puck past Colorado goalie Semyon Varlamov during a scramble in front of the net.
The Oilers added another power-play goal at 18:05 of the first as Eberle picked the top corner on a shot from the top of the circle for his third of the season.
Source: Associated Press