St Mawes (Cornish: Lannvowsedh) is a village on the end of the Roseland Peninsula, in the eastern side of Falmouth harbour, on the south coast of Cornwall, England.

The village, formerly two separate hamlets, lies on the east bank of the Carrick Roads, a large waterway created after the Ice Age from an ancient valley which flooded as the melt waters caused the sea level to rise.

St Mawes was once a busy fishing port, but the trade declined during the 20th century and the village now serves as a popular tourist location, with many properties functioning as holiday accommodation.

St Mawes Castle is a well-preserved coastal fortress from the time of Henry VIII, built to counter the invasion threat from the Continent.

Charles Henderson, writing in 1925, says of St Mawes, "an ancient fishing town which in late years has assumed the different and more sophisticated character of a watering place".

and a ship with three masts the sail furled in the dexter base of the second, with the legend "Commune Sigillum Burgi de St. Mawes al Mauditt.