Neff is a surname of German (also Naf, Naef, Kneff), Swiss (also Naff, Naffe, Nafe) or Czech origin. It may refer to:
- Charles D. Neff (1922–1991), American Mormon missionary and humanitarian
- Christophe Neff (born 1964), German geographer
- Donald Neff (contemporary), American journalist
- Dorothea Neff (1903–1986), Austrian stage and film actress
- Felix Neff (1798–1829), Swiss Protestant divine and philanthropist
- Francine Irving Neff (1925-2010), 35th Treasurer of the United States 1974–77
- Garrett Neff (born 1984), American fashion model
- Henry H. Neff (born 1973), American author and illustrator
- Jacob H. Neff (1830–1909), American politician; lieutenant governor of California 1899–1903
- Jay H. Neff (1854–1915), American newspaper publisher; mayor of Kansas City 1904–05
- Jean-Marie Neff (born 1961), French racewalker
- John Neff (American football) (before 1907-1938), American college football coach
- John Neff (investor) (born 1931), American investment manager
- Lucas Neff (born 1985), American actor
- Lyle Neff (born 1969), Canadian poet and journalist
- Marcus Neff (1826–1896), American settler in Oregon; respondent in the U.S. Supreme Court case of Pennoyer v. Neff
- Ondřej Neff (born 1945), Czech science fiction writer and journalist
- Pat Morris Neff (1871–1952), American politician from Texas; governor of Texas 1921–25
- Ray Neff (contemporary), American professor; proponent of alternative theories about the assassination of Abraham Lincoln
- Tom Neff (born 1953), American film executive, director, and producer
- Vladimír Neff (1909–1983), Czech writer and translator
- Wallace Neff (1895–1982), American architect
- Wolfgang Neff (1875-1936), Czech film director
Usage examples of "neff".
Emery Neff found that appraisal, scanned it, and jumped to the logical conclusion: that McKinley was a crook, lowballing so she could buy the books for a song.
Neff had stumbled into a gold mine, because not only had the codebreakers worked on Russian codes and ciphers, but the castle contained a German Foreign Office signals intelligence archive.
Neff couldn't be that weird a name anyway, only four letters, not like Shittendookus or Horecake, there must be thousands of Neffs, if you're talking coast to coast.