The blast, which occurred in Jakobsberg in the north west of the greater Stockholm area, smashed windows and damaged the front door of the cinema, also causing parts of the roof to be destroyed.
Police are unsure of who is responsible for the detonation, or what their motivation may be.
“We are currently unaware if it was some kind of gunpowder or something else that was used,” Fredrik Ladenstedt of the Norrort Police told the TT news agency.
Witnesses have explained how they heard a loud bang outside the Falken cinema shortly after midnight, followed by billowing smoke.
Police arrived on the scene soon after, with their only lead being a red car that was seen leaving the cinema following the blast. The car has still not been identified or found.
Emergency services were also quick to the scene, however left shortly after upon confirming there was no risk of fire.
Police have combed the area for evidence, collecting traces of the explosives for further forensic analysis.
An investigation has been launched by local police.