Beauchastel (French pronunciation: [boʃastɛl][3]) is a commune in the Ardèche department in the Auvergne-Rhône-Alpes region of southern France.

The east of the commune includes a portion of the Île Saint-Thimé in the Rhône river which is also the departmental border with Drôme.

The commune consists of a large urban area along the banks of the Rhône with farmland south of the Eyrieux and forested hills for the rest.

There is a dam on the main branch of the Rhône with an electricity generating station: the Centrale Electrique de Beauchastel.

[9] The commune takes its name from the castle "Bel Castrum" built in the 12th century by the Lords of Retourtour and Briand.