Mawnan is a village and civil parish in south Cornwall, England, United Kingdom. It is 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. The church town of the parish is Mawnan Church, also known simply as Mawnan, and the only large village in the parish is Mawnan Smith, approximately three miles south of Falmouth.