Gwynn is a census-designated place (CDP) in Mathews County, Virginia, United States. As of the 2020 census, Gwynn had a population of 578. Gwynn is located on Gwynn's Island, north-northeast of Mathews. Gwynn has a post office with ZIP code 23066.
Gwynn was first listed as a census designated place in the 2010 U.S. census.