MacArthur or Macarthur is a surname, originating with the Scottish Clan MacArthur and now spread through English-speaking countries. Notable people with the surname include:

Business

• Catherine T. MacArthur (1909–1981), American businesswoman, philanthropist, wife of John D. MacArthur
• Elizabeth Macarthur (1766–1850), Australian businesswoman, wife of John Macarthur (wool pioneer)
• Hannibal Hawkins Macarthur (1788–1861), Australian businessman and politician
• J. Roderick MacArthur (1920–1984), American businessman and philanthropist
• John Macarthur (wool pioneer) (1767–1834), Australian businessman, politician, and soldier
• John D. MacArthur (1897–1978), American businessman and philanthropist

Entertainment

• Charles MacArthur (1895–1956), American playwright and screenwriter
• James MacArthur (1937–2010), American actor

Literature

• John F. MacArthur (b. 1939), American evangelical minister and author
• John R. MacArthur (b. 1956), American journalist

Military

• Arthur MacArthur, Jr. (1845–1912), American military leader and father of Douglas MacArthur
• Arthur MacArthur III (1876–1923), American naval officer and brother of Douglas MacArthur
• Douglas MacArthur (1880–1964), American military leader and U.S. Army General of the Army
• Edward Macarthur (1789–1872), Anglo-Australian general and administrator
• George MacArthur-Onslow (1875–1931), Australian general
• James Macarthur-Onslow (1867–1946), Australian general, politician and company director

Politics

• Arthur MacArthur, Sr. (1815–1896), American lawyer, judge, and politician
• Douglas MacArthur II (1909–1997), American diplomat

Sports

• Clarke MacArthur born 1985), Canadian hockey player
• Ellen MacArthur (born 1976), British yachtswoman
• Mac MacArthur (1862–1932), Scottish baseball player

Science

• John Stewart MacArthur (died 1920), chemist from Glasgow
• Robert MacArthur (1930–1972), American ecologist
• William Macarthur (1800–1882), Australian botanist and vigneron

Other people

• Jean MacArthur (1898–2000), second wife of Douglas MacArthur

Fictional Characters

• MacArthur, a character from The Ridonculous Race