Firefighters have contained a large grass fire burning 25km South West of Goulburn this afternoon.

At about 1pm, NSW Rural Fire Service were called to reports of a grass fire on Collector Road, Currawang.

Fire crews arrived quickly and reported that the fire had already grown to 100 hectares in size and was moving quickly under extreme fire weather conditions.

Further resources were deployed to the fireground and firefighters worked hard to prevent the fire from crossing Curawang Road to the East.

The fire was contained just before 5pm this afternoon with the assistance of water bombing aircraft and heavy plant.

Crews, supported by heavy plant machinery will continue to strengthen containment lines this evening.

The NSW Rural Fire Service have said that there is no threat to nearby properties at this time.