Emergency services were called to an incident off Victoria Rd, St Kilda, at 2.24am.
A silver Nissan was located on fire in the access drive next to the St Clair Scout Group Hall.
Fire and Emergency southern communications shift manager Lyn Crosson said crews from Lookout Point and St Kilda thought the car "was well alight on arrival".
Crew could not locate anyone at the scene in relation to the incident, she said.
Ms Crosson said the incident had been referred to police as crew thought "the fire was a bit suspicious".
A police spokeswoman said they were unable to comment further on the issue, but were following lines of enquiry into the incident.