Ewa Pajor and Salma Paralluelo both scored twice as Barcelona outclassed Lyon to be crowned European champions for the fourth time in their history.
Pajor's double took her campaign total to 11 in the Champions League, more than any other player in the competition, and put her side on course for victory despite Barca being second best for over an hour of the tie.
But their quality blew Lyon away late in the second period, Salma Paralluelo adding two distinctive strikes of her own to put the game well beyond Jonatan Giraldez's deflated side. The scoreline was perhaps harsh but a product of Barca's wonderful finishing ability after an usually underwhelming start.
Last year's runners-up found it difficult to establish any proper rhythm in a trying first half in Oslo, Lyon stifling them by pressing hard and high. It's a level of subordination the Spaniards are rarely subject to in Liga F.
The space for Alexia Putellas to manoeuvre in midfield was limited while service to the forward players was only fleeting. Pajor still managed to carve out two of the first half's best chances, firing wastefully off target with both.
Lindsey Heaps thought she had punished Barca's sluggishness by firing home the game's opener from a Wendie Renard knockdown - until VAR intervened to rule the midfielder offside.
A goalless, largely frustrating, first period was conjuring memories of 2025's final in Lisbon, where Barcelona were suppressed by Arsenal before conceding to a late Stina Blacktenius decider.
But Pajor could only be delayed, not denied. It was finally her moment to shine on the biggest and most rewarding stage of them all.
The 29-year-old, five times a Champions League final loser, continued to get into good positions and eventually got her rewards. Patri Guijarro engineered Pajor's first with a precise pass to beat the offside trap before Paralluelo gifted the forward an easy second from close range.
Paralluelo herself then scored a sumptuous double in a half that got rather ugly for Lyon, as the young winger rifled home a precise third and finished expertly past Christiane Endler on the angle to put the game to bed.
They had the resilience of goalkeeper Cata Coll, with four saves in total, to thank for keeping them in the tie before proceeding to score four from five efforts on target - proving their superior standard well beyond doubt.
Few in the women's game are so clinical when it really matters. And none can claim to be as emphatic as this bold and brilliant Barcelona outfit.
Barcelona forward Ewa Pajor speaking to UEFA:
"I'm grateful. This is amazing; the best day of my life. I've played in six finals and finally, in Oslo, we did it.
"I am very proud and very thankful. From the start to the end, it was a hard game but we did so, so well.
"We fought for the win and that's what this team does every day; fight to be the best team in the world.
"This is the best day. My family is here and I am so happy. It's a special day and will be forever."
Barcelona forward Caroline Graham Hansen speaking to UEFA:
"Last season we lost the final but we kept the hunger and have gone step by step, even when everyone doubted us.
"It was close and Lyon had the initiative in the first half. Then we scored and kept control of the game, then we scored again, then they went for it and we got two more.
"Maybe the result [is not an entirely fair reflection], but overall we deserved it."
Lyon midfielder Lindsey Heaps speaking to UEFA:
"I'm proud of our team. We played very well, especially in the first half.
"We created chances but didn't take them, while Barcelona did. It's disappointing of course, and there will be a lot to reflect on, but in the end they scored the goals and we didn't."
"Full credit to Barcelona - they are one of the best teams in the world and it is always a pleasure to compete against them."
