The incident took place around 4:30 a.m. (1:30 a.m. GMT) off the northern coast of Corfu, between Greece and Albania, an official from the Greek coast guard's press office told Agence France-Presse (AFP).
Three patrol boats and three coast guard tugs were sent to the vessel on fire in the Ionian Sea.
"The captain of the Euroferry Olympia asked the passengers to leave the boat," police said. According to media reports, all the passengers of Euroferry Olympia have already evacuated the vessel in lifeboats.
They were being transported to the nearby Greek island of Corfu, said the Greek coastguard, leading the rescue operation.
The Euroferry Olympia sailed between Igoumenitsa in Greece and Brindisi in Italy.
The cause of the fire remains unknown. No casualties have been reported.
ZZ/PR