Alexander is a surname originating in Scotland. It is originally an Anglicised form of the Scottish Gaelic MacAlasdair. It is a somewhat common Scottish name and the region of Scotland where it traditionally is most commonly found is in the Highlands region of Scotland. Notable people with the surname include:

• AJ Alexander (born 1980), American model and Playboy Playmate
• A. V. Alexander, 1st Earl Alexander of Hillsborough (1885–1965), British politician
• Amir Alexander, historian
• Ana Alexander (born 1954), Cuban long jumper
• Ann Alexander Smith (born 1947), Louisiana educator
• Annie Lowrie Alexander (1864–1929), first licensed female physician in the Southern United States
• Archibald Alexander (1772–1851), first principle of Princeton Seminary
• Barton S. Alexander (1819–1878), U.S. Army brigadier general and engineer during the American Civil War
• Caleb Alexander (died 1828), American clergyman, writer, teacher
• Cecil Alexander (disambiguation), several people with this name
• Christopher Alexander (born 1936), Austrian architect
• Claudia Alexander (1959–2015), NASA scientist and project manager
• Conel Hugh O'Donel Alexander (1909–1974), British cryptanalyst, chess player, and chess writer
• Cory Alexander (born 1973), American National Basketball Association player from 1995 to 2005
• Courtney Alexander (born 1977), American National Basketball Association player from 2000 to 2003
• Danny Alexander (born 1972), British MP
• Dari Alexander (born 1969), American news anchor
• Devon Alexander (born 1987), American professional boxer
• Donald Alexander (lawyer) (1921–2009), American lawyer
• Donald Alexander (researcher) (1928–2007), Irish physician and researcher
• Dorothy Alexander, professional name of Dorothy Bohm (born 1924), naturalized British photographer
• Dottie Alexander (born 1972), American keyboardist
• Douglas Alexander (born 1967), British MP
• Duane Alexander (born 1940), American doctor
• Eben Alexander (author) (born 1953), American neurosurgeon, described his 2008 near-death experience
• Edward Porter Alexander (1835–1910), officer in the U.S. Army and Confederate States Army
• Ernie Alexander (born 1933), former member of the Louisiana House of Representatives
• Evan Shelby Alexander (1767–1809), American politician
• F. Matthias Alexander (1869–1955), Australian actor/orator, founder of the Alexander Technique
• Francesca Alexander (1837-1917), American illustrator, author, and translator
• Frank Alexander (cricketer) (1911–2005), Australian cricketer
• Franz Alexander (1891–1964), psychoanalyst
• Fred Alexander (rugby union) (1870–1937), South African rugby union player
• Gary Alexander (disambiguation), several people with this name
• Grover Cleveland Alexander (1887–1950), baseball player
• Gus Alexander, (1934–2010), Scottish footballer
• Harold Alexander (1900-1987), American politician
• Harold Alexander, 1st Earl Alexander of Tunis (1891–1969), British general
• Harvey Alexander, baseball player
• Holmes Alexander (1906–1985), American historian, journalist, and columnist
• Horace Alexander (1889–1989), English ornithologist
• James Waddel Alexander (1804–1859), American Presbyterian minister and theologian
• James Waddell Alexander II (1888–1971), mathematician
• Jason Alexander, stage name of American actor Jason Scott Greenspan
• Jason Allen Alexander, ex-husband of Britney Spears
• Jeffrey C. Alexander (born 1947), American sociologist
• Joe Alexander (disambiguation), several people with this name
• Joseph Alexander (disambiguation), several people with this name
• John White Alexander (1856–1915), American artist
• Lamar Alexander (born 1940), U.S. Senator from Tennessee
• Lincoln Alexander (1922–2012), Canadian politician
• Lloyd Alexander (1924–2007), American author
• Lucy Alexander (born 1970), British television presenter
• Manny Alexander (born 1971), baseball player from the Dominican Republic
• Margie Alexander (1948–2013), American singer
• Neil Alexander (born 1978), Scottish footballer
• Patrick Young Alexander (1867–1943), British aviation pioneer
• Peter Alexander (Austrian actor and singer) (1926–2011), Austrian singer and actor
• Randy Alexander (born 1951), American politician
• Richard D. Alexander (born 1930), professor and curator emeritus at the Museum of Zoology of the University of Michigan in Ann Arbor
• Rex Alexander, American college sports coach
• Robert P. Alexander (1904–1985), American philatelist
• Ross Alexander (1907–1937), American actor
• Samuel Alexander (1859–1938) Australian/British philosopher and essayist
• Sarah Alexander (born 1971), British actress
• Shane Alexander, 2nd Earl Alexander of Tunis
• Shaun Alexander (born 1977), American football player
• Stan Alexander (born 1905), English footballer
• Victor Alexander (born 1969), American basketball player
• Wilfred Backhouse Alexander (1885–1965), English ornithologist
• William Alexander (bishop) (1824–1911), Primate of All Ireland
• William Alexander (rugby player) (1874–1937), Wales international rugby player
• William Alexander, 1st Earl of Stirling (c.1567-1640), Scottish noble
• Willie Alexander (American football) (born 1949), American football player