Jonathan, Johnathan, or Jon Williams may refer to:
Arts and entertainment
Jonathan Williams (antiquary) (died 1829), Welsh antiquary
Jonathan Williams (poet) (1929–2008), American poet, publisher, essayist, and photographer
Jonathan Williams (horn player) (born 1957), British horn player
Jonathan Williams (pianist) (born 1974), American pianist, songwriter and vocalist
Jonathan Williams (filmmaker), Canadian web series creator, writer and director
Jon Williams, video game programmer, creator of Jet-Boot Jack
A pseudonym used by science fiction author Walter Jon Williams when writing historical fiction
Basketball
Johnathan Williams (born 1995), American basketball player who has played in the NBA
Jonathan Williams (basketball, born 1995), American basketball player who played in college at Toledo
Jonathan Williams (basketball, born 1996), American basketball player who played in college at VCU
Gridiron football
Jon Williams (American football) (born 1961), American football player
Jonathan Williams (running back, born 1988), American football player in the Canadian Football League
Jonathan Williams (running back, born 1994), American football player in the National Football League
Jonathan Williams (defensive lineman) (born 1985), American football defensive lineman in the Canadian Football League
Other sports
Jonathan Williams (hurdler) (born 1983), American hurdler who has represented Belize
Jonny Williams (born 1993), Wales international footballer
Jonathan Williams (racing driver) (1942–2014), Formula 1 driver
Other
Jonathan Williams (engineer) (1751–1815), American businessman, military figure, politician, writer and engineer
Jonathan Williams (priest) (born 1960), Welsh Anglican priest
Jonathan Williams (Vermont politician)
Jonathan "Caveman" Williams, person killed in the 2003 John McDonogh High School shooting