Myles Fitzhugh Longfield Ponsonby, 12th Earl of Bessborough (born 16 February 1941), is a British peer.
He is the son of Arthur Ponsonby, 11th Earl of Bessborough, and his wife Patricia Minnigerode, daughter of Col. Fitzhugh Lee Minnigerode.
He was educated at Harrow School and Trinity College, Cambridge. Later he was invested as a Fellow of the Institute of Chartered Accountants.
In 1972 he married Alison Marjorie Storey, daughter of William Storey, and together they have three children:
The heir apparent to the earldom is the current earl's eldest son, Frederick Ponsonby, Viscount Duncannon. In 2005 he married Emily Mott, daughter of Dr.