- For the origin and usage of the name Sidney, see Sidney (name origin)
Sidney as a surname may be
- Algernon Sidney, republican under Charles II
- Donald Sidney-Fryer, American poet
- George Sidney, American film director
- Henry Sidney (1529-1586), father of Mary, Philip and Robert, Earl of Leicester
- Hilarie Sidney, musician
- Mary Sidney, Countess of Pembroke
- Philip Sidney, poet and courtier under Elizabeth I
- Sylvia Sidney, American actress
As a family name in the English aristocracy:
- Robert Sidney, 1st Earl of Leicester (d.1626)
- Robert Sidney, 2nd Earl of Leicester (1595-1677)
- Philip Sidney, 3rd Earl of Leicester (1619-1698)
- Robert Sidney, 4th Earl of Leicester (1649-1702)
- Philip Sidney, 5th Earl of Leicester (1676-1705)
- John Sidney, 6th Earl of Leicester (1680-1737)
- Jocelyn Sidney, 7th Earl of Leicester (1682-1743)
- Henry Sydney, 1st Earl of Romney, also spelled Sidney
- Philip Charles Sidney, 1st Baron De L'Isle and Dudley (1800 - 1851)
- Philip Sidney, 2nd Baron De L'Isle and Dudley (1828 - 1898)
- Philip Sidney, 3rd Baron De L'Isle and Dudley (1853 - 1922)
- Algernon Sidney, 4th Baron De L'Isle and Dudley (1854 - 1945)
- William Sidney, 5th Baron De L'Isle and Dudley (1859 - 1945)
- William Philip Sidney, 6th Baron De L'Isle and Dudley (1909 - 1991)
- Philip John Algernon Sidney, 2nd Viscount De L'Isle (b. 1945)
- Hon. Philip William Edmund Sidney (b. 2 Apr 1985)
