NSW Rural Fire Service (RFS) volunteers are on scene of a fire near Galong on Bobbara Road.
Firefighters first responded to the blaze at 1.30pm on Wednesday and 18 appliances have been called in to bring the fire under control.
The fire has burned through around 110 hectares.
South West Slopes RFS Zone district co-ordinator Inspector Tom McDevitt said volunteers were working on containment.
He said the fire was located on private land however no property or people were under threat from the fire at the moment and no property had been reported lost.
As well as firefighters, there are three aircraft operating to support volunteers work as well as various heavy plant including graders, bulldozers and bulk water carriers.
Inspector McDevitt said there was no information on the cause of the fire as yet.
A total fire ban remains in place for the South West Slopes RFS Zone until midnight on Wednesday.