Frederick David Ely (24 September 1838-6 August 1921) was a member of the US House of Representatives (R-MA 9) from 4 March 1885 to 3 March 1887, succeeding Theodore Lyman III and preceding Edward Burnett. Born in Wrentham, he practiced law in Dedham before serving in the state and national legislatures and as a municipal judge in Boston.