Emergency services attended a set of units in King St, Warragul on Thursday morning after receiving reports one of the units was on fire.
CFA members arrived shortly after 8.50am and firefighters controlled the blaze in about 30 minutes. Police said the unit was badly burnt.
Police said the tenant of the unit was at work at the time and no one was injured. Occupants of nearby units were evacuated and assessed Ambulance Victoria paramedics.
Electricity to the group of units will need to be restored. Other affected tenants have been temporarily re-housed.
Investigators confirmed the fire originated in the living room but have not determined how the fire started.
The fire has been deemed not suspicious.