A Fire and Emergency New Zealand spokesman said crews from Balclutha, Milton and Kaitangata were called to the fire in Hospital Rd at 12.45pm.
The single-storey house was well ablaze when firefighters arrived, but contained by 1.40pm, the spokesman said.
One firefighter received minor injuries at the scene and was treated by St John ambulance staff.
A water tanker from Balclutha attended, along with four other fire appliances, he said.