Fatso may refer to:
Animals The proper name of Keyboard Cat, a cat who became the subject of an Internet meme Fatso (crocodile), a saltwater crocodile in captivity in Western Australia
Arts, entertainment, and media Fictional characters Sergeant "Fatso" Judson, a character in the 1953 American film From Here to Eternity Fatso, a member of the Ghostly Trio and one of Casper the Friendly Ghost's uncles Fatso, a wombat from the Australian television series A Country Practice The Mancubus or Fatso, a character in the video game Doom II Fatso the Fat-Arsed Wombat, an unofficial mascot for the Sydney 2000 Summer Olympics Films Fatso (1980 film), an American film directed by Anne Bancroft Fatso (2008 film), a Norwegian film directed by Arild Fröhlich Fatso!, a 2012 Indian film directed by Rajat Kapoor
Literature Fatso, a 1987 autobiography by retired American football player Art Donovan FAT!SO?, a 1998 book by Marilyn Wann
Music Fatso (band), a band who featured on the TV series Rutland Weekend Television
People Leonard DiMaria (born 1941), New York mobster nicknamed Fatso Vincenzo Licciardi (born 1965), Italian criminal clan boss nicknamed "'o Chiatto" (Fatso)
Other uses FTO gene, or Fatso, a gene linked to obesity and type 2 diabetes Fatso the Fat-Arsed Wombat, an unofficial mascot of the Sydney 2000 Olympics Fatso (service), an online DVD rental service in New Zealand