Arngask is a civil parish in Perthshire, with the village of Glenfarg as its largest settlement. It lies in the south-east of the county, in the Ochil Hills and borders Fife and Kinross-shire. If forms part of a wider ecclesiastical parish of Abernethy and Dron and Arngask.
The parish includes of the upper reaches of the River Farg and has an area of .
At the 2011 census, the population of the civil parish was 931.