Melbourne restaurant destroyed by fire

A Melbourne Greek restaurant has been destroyed by fire and the owner says it's lucky it didn't happen later when customers were inside.

Smoke was billowing from the roof of the two storey Spitiko restaurant in South Melbourne when firefighters arrived on Wednesday afternoon.

Flames could be seen coming through the roof at the height of the blaze which took more than a dozen firefighters to bring under control.

Two staff inside the restaurant managed to escape as the flames took hold.

Restaurant owner John Ghionis said he hasn't yet been able to go inside and survey the damage.

"Lucky it didn't happen later in the night when there was customers," Mr Ghionis told Nine News.

"I'm just rapt that everyone's OK. Everything else can be fixed."

The fire is believed to have started in lower level and then quickly spread through the flue to the upper floor, the Metropolitan Fire Brigade says.

Firefighters managed to stop the blaze from spreading to nearby businesses.