Merritt Island is a census-designated place in Brevard County, Florida, United States. It is located on the east coast of the state on the Atlantic Ocean. As of the 2010 census, the population was 34,743. It is part of the Palm Bay – Melbourne – Titusville, Florida Metropolitan Statistical Area. The name "Merritt Island" also refers to the extent of the former island, which is now a peninsula. Merritt Island National Wildlife Refuge and NASA's John F.