Mawnan (Cornish: Maunan, meaning St Maunan) is a civil parish in south Cornwall, England, United Kingdom. It is situated in the former administrative district of Kerrier and is bounded to the south by the Helford River, to the east by the sea, and to the west by Constantine parish. The population was 1,454 in the 2001 census, rising slightly to 1,476 at the 2011 census.