Mariel Hadley Hemingway (born November 22, 1961) is an American actress and writer.
Hemingway was born in Mill Valley, California, the third daughter of Byra Louise (née Whittlesey) Hemingway and Jack Hemingway, a writer. Her sisters are Joan Hemingway (born 1950) and Margaux Hemingway (born 1954). Margaux, who became an actress and model, died of a barbiturate overdose in 1996 at age 42.
Her paternal grandparents were Hadley Richardson and writer Ernest Hemingway, whom she never met, as he committed suicide several months before she was born. She was named after the Cuban port of Mariel—a village that her father and grandfather visited regularly as sportsmen to fish. Her middle name was after her paternal grandmother.