Arnett is both a surname and a given name. Notable people with the name include:
Surname:
Benjamin W. Arnett (1838–1906), American educator, bishop, and elected official
Chuck Arnett (1928–1988), American dancer
Jeffrey Jensen Arnett (born 1957), American psychologist
Jon Arnett (1935–2021), American football player
Kaylea Arnett (born 1993), American diver
Peter Arnett (1934–2025), New Zealand-American journalist
Ross H. Arnett Jr. (1919–1999), American entomologist
Ulysses N. Arnett, American politician from West Virginia
W. David Arnett (born 1940), American astrophysicist
Will Arnett (born 1970), Canadian actor
William Arnett (1939–2020), American writer and art collector
Given name:
Arnett "Ace" Mumford (1898–1962), American football coach
Arnett Cobb (1918–1989), American jazz saxophonist
Arnett Howard (born 1959), American jazz musician
Arnett Moultrie (born 1990), American basketball player
Arnett Nelson (1892–1959), American jazz musician