Cayley may refer to:
- Kaylee, which Cayley is a variation of
- Arthur Cayley (1821–1895), British mathematician
- Charles Bagot Cayley (1823–1883), British linguist and friend of Christina Rossetti
- George Cayley (1773–1857), English naturalist, physical scientist, engineer, inventor, politician, and pioneer of flight
- Hugh Cayley, Canadian journalist and politician, son of William and namesake of the village in Alberta
- Neville Henry Cayley (1853–1903), Australian artist
- Neville William Cayley (1886–1950), Australian author, artist and amateur ornithologist
- William Cayley, Canadian politician, father of Hugh
- Cayley, Alberta
- Cayley computer algebra system, designed to solve mathematical problems, particularly in group theory
- Cayley (crater), a lunar crater
- Mount Cayley, a volcano in southwestern British Columbia, Canada