MacKinnon finished the season with 140 points (51 goals, 89 assists) to pass Peter Stastny, who had 139 points for the Quebec Nordiques in 1981-82.
Cale Makar had an assist to become the 12th defenseman in NHL history with 90 points (21 goals, 69 assists) in a season for the Avalanche (50-25-7), who finished in third place in the Central Division. Valeri Nichushkin scored twice, and Justus Annunen made 25 saves.
The Avalanche will face the Winnipeg Jets in the Western Conference First Round of the Stanley Cup Playoffs.
Dylan Holloway scored for the Oilers (49-27-6), who lost four of their final five (1-3-1) and finished in second place in the Pacific Division. Stuart Skinner allowed four goals on 13 shots before being replaced by Calvin Pickard at the start of the second period. Pickard made 14 saves in relief.
The Oilers will face either the Los Angeles Kings or Vegas Golden Knights in the first round of the playoffs.
Nichushkin scored to make it 1-0 Colorado when he one-timed a pass from Artturi Lehkonen at the right dot at 1:19 of the first period.
Mikko Rantanen extended the lead to 2-0 with a wrist shot from just below the right dot that went short side over the shoulder of Skinner at 5:48.
Nichushkin scored on the power play to make it 3-0 at 7:37, redirecting a centering pass from MacKinnon at the right side of the crease.
Josh Manson made it 4-0 when shot from the blue line deflected off Oilers defenseman Cody Ceci at 10:17.
Holloway scored to make it 4-1 with a power-play goal at 15:22 when he deflected Philip Broberg’s point shot from between the hash marks.
Zach Parise made it 5-1 when he dropped to his knee atop the crease and one-timed a behind-the-net pass from Ross Colton at 12:00 of the second period.
Avalanche forward Jonathan Drouin left the game at 18:11 of the second period with a lower-body injury.
The Oilers did not play their top seven scorers: forwards Connor McDavid, Leon Draisaitl, Zach Hyman, Ryan Nugent-Hopkins and Evander Kane; and defensemen Evan Bouchard and Mattias Ekholm.
