Riec-sur-Bélon (; ) is a commune in the Finistère department of Brittany in north-western France.
Inhabitants of Riec-sur-Bélon are called in French Riécois.
The municipality launched a linguistic plan concerning the Breton language through Ya d'ar brezhoneg on 16 December 2008.
Riec-sur-Bélon is twinned with: