Valparaiso is a city in Okaloosa County, Florida, United States. It is part of the Crestview–Fort Walton Beach–Destin, Florida Metropolitan Statis…Valparaiso is a city in Okaloosa County, Florida, United States. It is part of the Crestview–Fort Walton Beach–Destin, Florida Metropolitan Statistical Area. As of the 2020 census, the city population was 4,752, down from 5,036 at the 2010 census.