Police launched a murder investigation on Monday morning after forestry workers found the man's body inside a light goods vehicle parked on a small road in the woods near Filipstad in western Sweden.
"Circumstances at the scene lead police to suspect murder," said a statement on their website.
But forensic teams found, on examining the body, that the man, who has been identified as in his fifties and a resident of the Västra Götaland region, was not killed. Police no longer suspect murder.
The Aftonbladet tabloid reported earlier on Monday that the body had been found with its head severed. However, police did not confirm those reports.