Locoal-Mendon (French pronunciation: [lɔkwal mɛ̃dɔ̃]; Breton: Lokoal-Mendon) is a commune in the Morbihan department of Brittany in north-western France.

[3] Known as Locus Sancti Guitali in 1037 and Sanctus Gudualus in 1387.

From the Breton lok which means hermitage (cf.

: Locminé), and Goal which is a name for the Breton saint Gudwal, Gurval or Gutual, eponym also of Gulval.

In 2008, there was 17,81% of the children attended the bilingual schools in primary education.