It's the first time an SHL match has required four periods of overtime, therefore making overtime longer than regulation. It beats the previous SHL record of 119:16 set in March 1997 between Leksand and Farjestad.
The match began in typical fashion - the top seeds, Skelleftea, needed one fewer quarter-final match to get past Malmo than Lulea needed to see off Frolunda, and that freshness seemed to serve the home side well when they went ahead in the third minute.
Max Krogdahl sent the puck in front from the blue line, and Lars Bryggman connected with it perfectly to score. But Lulea responded well, and were level six minutes later when Isac Hedqvist won possession deep in opposition territory, allowing Brian O'Neill to set up Brendan Shinnimin to equalise.
1-1 was how things stayed until six minutes to go in period two, when Par Lindholm won a face-off in the attacking zone, knocking it back to Pontus Johansson, who suddenly had time and space to power the puck home and restore Skelleftea's advantage.
A slashing penalty late in the second against Oskari Laaksonen was punished 18 seconds into period three, as Johansson laid the puck on a plate for Oscar Lindberg in space, who put the home side two up.
But that only served to start the Lulea fightback - the visitors were back within one when Oskar Engsund's attempted pass from the blue line took a huge deflection off Mans Forsfjall's skate, taking it past Strauss Mann.
Then, a holding call against Valter Lindberg gave Lulea the chance they needed to craft an excellent team move to unlock the home defence, as Mathias Brome squared for Frederic Allard to make it 3-3 on the powerplay with nine minutes remaining.
Overtime could have lasted less than two minutes, but Bryggman's strike came back out off the post, and only a superb Matteus Ward save denied Viktor Grahn from wrapping it up a minute later. But those were the best chances for either side across 20 minutes, and a fifth period was needed.
Lulea failed to make use of a powerplay late in the fourth period following slashing by Allard, and they were nearly punished in the fifth when Max Krogdahl's centre was deflected over Ward but landed on the roof of the net.
Both sides had a man penalised late on for unsportsmanlike conduct as tempers began to flare, but still neither side could find a way through. Oliver Okuliar, Rickard Hugg and Lindholm all passed up big chances in period six, as the old record for longest match was passed and the 120-minute mark was hit.
Finally, two minutes and 18 seconds into period seven, Skelleftea got the winner which they perhaps deserved - Krogdahl shot wide but it was picked up behind the net by Emil Djuse, he set the puck back for Andreas Johnson, whose effort had enough on it to beat Ward and seal a hard-fought 4-3 win.
That was Skelleftea's 53rd shot on goal in the game, while Lulea managed 38. To put in so much effort and come away with nothing will be tough for the reigning champions, who will have to do it all again away from home in game two on Thursday 9th April.
Sweden's SHL joins Finland's Liiga in breaking the record for its longest match this postseason, after Assat beat SaiPa after 125 minutes in game one of their quarter-final series.
The opening game of the other SHL semi-final, Vaxjo vs Rogle, will be played tonight, Wednesday 8th April.