Emergency services were called to the mosque in Eslöv, a small city in the south of the country, at around 3.15am on Monday.
It is understood that the blaze began after flammable liquid caught fire in one of the rooms in the building.
Firefighters quickly arrived at the scene and were able to prevent the fire spreading, although the flames still caused minor damage to the building. Firefighters suspect foul play.
"There is no possible natural explanation for this type of fire to break out by itself", fire department spokesman Gustaf Sandell told Sveriges Radio.
Police officers cordoned off the area and have launched an investigation. Photo: TT
The fire comes less than a week after several people were hurt in a separate fire at a mosque in Eskilstuna in central Sweden on Christmas Day. Police say they are unable to confirm whether the blaze there was started on purpose.