Fierro is a Spanish and Italian surname meaning "iron". Notable people with the surname include:
Daniel Fierro, Political consultant
Eric Fierro, Complex Litigation & Electronic Discovery Attorney
Fanny Carrión de Fierro, Ecuadorian writer and literary critique
Gonzalo Fierro (born 1983), Chilean football player
Josefina Fierro de Bright (1914–1998), Mexican-American activist
Juan Fierro (born 1974), Chilean road cyclist
Julia Fierro (born 1976), Italian-American novelist and founder of The Sackett Street Writers' Workshop
Luis Fierro (born 1964), Ecuadorian economist and social development specialist
Martha Fierro (born 1977), Ecuadorian chess champion
Martin Fierro (saxophonist) (1942–2008), saxophonist
Rodolfo Fierro (1880–1915), General in the Pancho Villa army during the Mexican Revolution
Rodrigo Fierro, Ecuadorian M.D., writer and politician, former Minister of Health of Ecuador.
Aurelio Fierro (1923–2005), Italian actor and singer
Fictional characters:
Martín Fierro, a fictitious character in a poem by Argentine José Hernández
