Ryan Getzlaf, Radek Dvorak and Sami Vatanen scored for the Ducks (29-11-6), who won back-to-back games in Edmonton to capture their first divisional title since 2007 — the year they went on to win the Stanley Cup.
The Oilers (17-21-7) have now lost eight of their last nine and seem destined for yet another high draft pick in the off-season.
Anaheim started the scoring six minutes in on the power play as Getzlaf picked the puck out of a scramble out front and calmly slipped his 15th of the season past Oilers starter Nikolai Khabibulin.
The Ducks went up 2-0 at 11:48 as Emerson Etem was left alone to send a beautiful no-look backhand pass to Dvorak for an easy tap-in.
The only good chance in a listless and scoreless second period belonged to the Ducks, as Kyle Palmieri was alone in tight but stoned on a quick glove save by Khabibulin with two minutes remaining.
The shots were 18-16 in Anaheim’s favour after 40 minutes.
The Ducks took a three-goal lead four minutes into the third frame as Vatanen sent a long shot through traffic that found the top corner of the net.
Next up for the Oilers is a home date against the Chicago Blackhawks on Wednesday. The Ducks finish off a four-game road trip in Vancouver on Thursday.
Notes: The Ducks officially eliminated the Oilers from playoff contention on Sunday, making them the team with the longest active post-season drought, having missed the playoffs for the last seven seasons dating back to their Game 7 loss in the Stanley Cup finals to the Carolina Hurricanes in 2006… Oilers centre Eric Belanger made his return from a groin injury to play his first game since missing the last 13 contests. He took the place of Magnus Paajarvi, who was nursing a foot injury… Also out for the Oilers were three players presumably gone for the remainder of the season — Ryan Nugent-Hopkins (shoulder), Ales Hemsky (foot) and Lennart Petrell (leg)… Significant absences from the Anaheim lineup included defensemen Luca Sbisa (lower body) and Sheldon Souray (lower body), who missed his second straight game against his former team. Ducks forward Bobby Ryan was a late scratch with an illness.