The newspaper published a story on Saturday detailing the suicide of 32-year-old Anders Göthberg, a guitarist in the band Broder Daniels, who took his own life a week earlier.
The story was featured on Expressen's front page and on flysheets posted in the windows of newsstands and press shops.
But the picture next to a banner headline reading “32-year-old pop star took his own life” was a photo of current Broder Daniels singer Henrik Berggren and former drummer Lars Malmros, now with the band Hästpojken, and not an image of Göthberg.
Expressen was quick to apologize for error, posting a message on its website on Saturday, and publishing an apology in Sunday's printed edition.
“We deeply regret and apologize unreservedly for this discomfort this mix up has caused,” wrote Expressen's responsible editor Per-Anders Broberg on the paper's website.
Malmros's manager Hansi Friberg was not amused by the incident.
“I've never seen anything like it,” she told the media magazine Resumé.
“Obviously, it's been very unpleasant both for Lars Malmors's family, and for the relatives of Anders Göthberg.”
Friberg went on to tell Resumé that she felt Expressen's apology wasn't enough and that she planned to take up the matter with a lawyer first thing on Monday.