Jefferies may refer to:
Companies:
- Jefferies & Company, a global investment bank and institutional securities firm
People:
- Alan Jefferies (born 1957), Australian writer
- Chris Jefferies (born 1980), American basketball player
- Cindy Jefferies, English writer of fiction for children
- Darren Jefferies (born 1993), English footballer
- Gregg Jefferies (born 1967), American baseball infielder
- Jim Jefferies (born 1950), British football manager
- Matt Jefferies (1921-2003), American artist, set designer and writer
- Richard Jefferies (1848–1887), English nature writer
- Richard Jefferies (curator), English curator of the Watts Gallery (1985 to 2006)
- Richard Jefferies (screenwriter), American screenwriter, film producer, film director and editor
- Richard Manning Jefferies (1889–1964), American state legislator and the 101st Governor of South Carolina (1942 to 1943)
- Dick Jefferies, paleontologist
- Thomas Jeffries, also known as Thomas Jefferies (died 1826), Australian outlaw & prisoner