There were just over 5,200 people in the stands at Scandinavium in Gothenburg, compared with the previous attendance record of 4,020.
When it was 2-0 in the set in Friday's match against Montenegro and Sweden were down in the third set, the crowd was a huge boost, according to Isabelle Haak.
"You couldn't have imagined what it would look like, but you felt the support for every point we scored," the star said.
During the weekend, even more people are expected to come to the arena to watch Sweden play.
We have just begun, Isabelle Haak said.
Sweden eventually won 3-0 in the set. The next match will be played on Saturday against Slovakia.
