Plouay (French pronunciation: [pluɛ]; Breton: Ploue) is a commune in the Morbihan department in Brittany in north-western France.

Inhabitants of Plouay or Ploue are called Plouaysiens in French and Plouead (Ploueiz), Ploueadez (-ed) in Breton.

The marquis of Pontcallec had in the seventeenth century in the village of Plouay court, prison, pillory and gallows with four pillars.

The municipality launched a linguistic plan through Ya d'ar brezhoneg on 10 February 2006.

In 2008, 11.56% of the children in Plouay attended Breton-French bilingual classes in primary education.