The accident occurred north of Dalälvsbron just after 1am. It is not clear why the car drove off the road, according to local police.
Another man died in a head-on collision outside Varberg. He was taken to Varberg hospital with serious following the accident but later died. The driver of the other car was hurt, but police said that his injuries were not life-threatening.
A number of other people were injured in accidents across the country but traffic police said that the Christmas holiday had begun “unusually calmly” on the roads.
However, on Christmas Eve morning, the Swedish Meteorological and Hydrological Institute (SMHI) warned of the risk of black ice from the afternoon onwards, due to wet roads and rapidly falling temperatures.
The risk is greatest for motorists in the south and middle of Sweden, warned SMHI meteorologist Åsa Bodén.