The Ducks (30-4) won 21-25, 30-28, 25-22, 25-19 to advance to the title game Saturday night against third-seeded Texas, a five-set winner over unseeded Michigan.
Alaina Bergsma and Katherine Fischer each had 16 kills for the Ducks, who are appearing in their first Final Four. Bergsma added 15 digs, Fischer 12 as Oregon was 63 percent on team attacks.
"I'm probably not supposed to say this, but I have no idea how we won that match because they are really good," Oregon coach Jim Moore said about the Nittany Lions.
Ariel Scott had 18 kills for Penn State (33-3).
Oregon beat Penn State for the second straight season. The Ducks won last season's opener over the Nittany Lions, ending their 94-match home winning streak.
This time, the Ducks ended the Nittany Lions' bid to win their fifth national title in six years.
Of course, Oregon had many of its owns strengths to speak of.
The Ducks entered the game leading the nation in team kills per set (15.97) and team assists (14.91). Most of that was due to Oregon's mix of quickness and improvisation that won all but two sets in the tournament.
Penn State nonetheless presented a huge challenge, having lost just one tournament set coming in.
There were five lead changes and 14 ties in the opening frame, the last at 20-20 as the Nittany Lions got a point off an attack error. Penn State scored four in a row off Oregon mistakes and won it on a Katie Slay kill on an assist from Micha Hancock, the All-American setter.
Oregon controlled most of the second set, building a 20-10 lead as Penn State struggled on offense and defense. The Nittany Lions also played for a stretch without Hancock, who turned her left ankle after coming down on Fischer's foot.
But Penn State tied the set with a 14-4 run and traded the lead with Oregon before the Ducks finally won it on Brenner's kill.
Oregon led 19-16 in the third but Penn State rallied to tie the game at 19 and again at 21. A bad set from Penn State's Dominique Gonzalez gave Oregon the go-ahead point before Fischer added two kills for a 24-22 lead and the eventual set win.
Oregon's serve befuddled Penn State throughout but especially in the final two games, as the Nittany Lions struggled to set up opportunities and seemed out of place for many returns.
"I thought we had a few opportunities in the second game that we let slip away," Penn State coach Russ Rose said. "I just think we lost a lot of confidence and steam at that point."
Texas won the first semifinal 25-11, 21-25, 23-25, 25-12, 15-11.
Bailey Webster had 18 kills and Haley Eckerman added 16 for the Longhorns.
Texas (28-4) dominated the first and fourth sets and took a 4-0 lead in the final set before Michigan tied it at 8. After a timeout, the Longhorns won three straight points and held off the Wolverines.
"The fans got their money's worth. What a battle," Texas coach Jerritt Elliott said.
"I've been saying it, that we're good in the crunch. You never see them give up. Even though we give up games, you can just see that they stay in their routine and just battle."
Sarah Palmer had a career-high 31 digs for the Longhorns, 3-0 lifetime against the Wolverines.
Junior outside hitter Lexi Erwin had 26 kills and a career-high 87 attempts for unseeded Michigan (27-12), which was appearing in its first Final Four. Senior captain Claire McElheny added 15 kills and had a .419 hitting percentage.
Texas entered the semifinals having won 21 of 22 matches since a 6-3 start that included a loss to Penn State. That roll earned the Longhorns their fourth Final Four berth in the past five years with a bigger goal of closing the deal after blowing a 2-0 lead and losing to Penn State in the 2009 final.
The Longhorns wasted no time carrying out their strategy, using their size and power to dominate the first set.
Webster had six kills, Khat Bell four and Eckerman three as Texas mounted several runs and put the set out of reach with seven straight points for a 14-5 lead. A 5-2 run clinched the 25-11 win for the Longhorns, with Webster adding two kills while their defense deny the Wolverines at the net.
Unfazed, Michigan improved its attack and won the next two sets with several small scoring spurts that provided a cushion against Texas.
Texas quickly seized the momentum and ran away with the fourth set with left-side help from Webster. Her presence created matchup problems for Michigan and the Longhorns took advantage for a .455 attack percentage en route to a dominating 25-12 win.
Having found their rhythm, the Longhorns grabbed the early advantage in the fifth set and didn't flinch after the Wolverines tied the set.
Michigan's loss ended a resilient run to its first Final Four, one that included overcoming several losing streaks before turning things around late in the season. The Wolverines definitely had found their groove over the past month, beating conference rival Michigan State twice and upending Stanford in the Berkeley Regional final.