Agonac (French pronunciation: [aɡɔnak]) is a commune in the Dordogne department in Nouvelle-Aquitaine in southwestern France.

It is situated on the small river Beauronne, 12 km (7.5 mi) north of Périgueux.

Agonac station has rail connections to Bordeaux, Périgueux and Limoges.

The settlements "Borie-Vieille" and "Les Cadagnes" have yielded prehistoric remains.

In the 11th century, the village was built on a hill controlling valleys with difficult access.