Daniell is a surname, and may refer to:
- Ave Daniell (1914-1999) American (gridiron) footballer.
- Charles Daniell (1827-1889) Major-General, British Army
- David Daniell (born 1929), biographer of William Tyndale
- David Daniell (born 1972), American guitarist and composer
- David Daniell (born 1989), English competitive cyclist
- Edward Thomas Daniell (1804-1842) English landscape painter and etcher
- Harold Daniell (1909-1967) British racing motorcyclist
- Henry Daniell (1894–1963), British actor
- Jim Daniell (1918-1983) American (gridiron) footballer
- John Daniell (1878-1963), English rugby player and Cricketer
- John Daniell (born 1972), New Zealand rugby player
- John Frederic Daniell (1790–1845), British chemist and physicist
- Marcus Daniell (1989- ) New Zealand tennis player
- Percy John Daniell (1889–1946), British mathematician
- Robert Daniell (1646-1718) Governor of North Carolina
- Samuel Daniell (1775-1811) English landscape painter
- Thomas Daniell RA (1749–1840), English landscape painter
- Warren Daniell (1826-1913) US Representative
- William Daniell RA (1769–1837), English landscape and marine painter, and engraver
- William Freeman Daniell (1818–1865), British army surgeon and botanist
Daniell may also refer to:
- Daniell cell, an electrochemical cell invented by John Frederick Daniell.
- Daniell integral, a generalized form of mathematical integral proposed by Percy Daniell.
- Daniell (crater), a lunar crater named after John Frederic Daniell.