Waldorf is a census-designated place in Charles County, Maryland, United States. Located 23 miles south-southeast of Washington, D.C., Waldorf is part of Southern Maryland. Its population was 81,410 at the 2020 census, making it the fourth-most populous community in the state and the largest community in Southern Maryland. Waldorf has experienced dramatic growth, increasing its population 16-fold from fewer than 5,000 residents in 1980 to its current population.