Fellsmere is a city in Indian River County, Florida, United States. It is home of the Fellsmere Frog Leg Festival and The National Elephant Center. Fellsmere is the first place in Florida where women were allowed to vote, in a 1915 municipal election.
The population was 5,197 at the 2010 census, up from 3,813 at the 2000 census. As of 2016, the estimated population was 5,547. Fellsmere is part of the Sebastian–Vero Beach Metropolitan Statistical Area.