Coolah Parish is a civil parish of the County of Napier,[3] a county in the central western part of New South Wales, Australia in Warrumbungle Shire.

[1] Before European settlement the area was occupied by the Gamilaroi and Wiradjuri peoples.

Allan Cunningham was the first British explorer to discover the area in 1823 while travelling Pandoras Pass over the Warrumbungle ranges to the Liverpool Plains.

On the northeastern side of the area is the Liverpool Range with the Coolah Tops National Park.

The town of Coolah, New South Wales is the main settlement of the parish.