Castell is a surname of English, French or Catalan origin. Notable people with the surname include:
Adela Castell (1864–1926), Uruguayan educator, writer, and poet Alan Castell (1943–2024), English cricketer David Castell, American record producer, musician and recording engineer Edmund Castell (1606–1685), English orientalist John Castell (aka John Castle), 15th-century Master of University College, Oxford, and a Chancellor of the university Jordan Castell, American football player José María Castell (1896–1981), Spanish footballer Lacksley Castell (1962–1984), Jamaican reggae singer Lluc Castell (born 2006), Spanish footballer Patricia Castell (1926–2013), Argentine actress Sir William Castell (born 1947), British businessman