Klug is a surname. Notable people with the surname include:
Johann Christoph Friedrich Klug (1775–1856), German entomologist
Bernd Klug (1914–1975), German naval officer
Al Klug (born 1920), American football player
Aaron Klug (born 1926), Lithuanian-born chemist
Brian Klug (fl. late 20th century), academic in U.K.
Howard Klug (fl. c. 2000), American clarinetist & academic
Scott L. Klug (born 1953), American politician
Bryan Klug (born 1960), English footballer
John Klug (born 1965), Australian footballer
Gerald Klug (born 1968), Austrian politician
Chris Klug (born 1972), American snowboarder
Gerard Christopher Klug, American game designer
Melissa Klug, Peruvian entertainer and vixen