- Sep 1 Olga de Haas, Dutch ballerina, dies as a result of anorexia nervosa at 33
- Sep 2 William Nebergall, American inorganic chemist (invented fluoride toothpaste), dies at 63 [1]
- Sep 5 Joe Negroni, American rock vocalist (Frankie Lymon & The Teenagers), dies of a brain hemorrhage at 37
- Sep 6 Adolf Dassler, German entrepreneur (founder sportswear company Adidas), dies at 78
- Sep 6 Tom Wilson, American record producer (Sun Ra; Bob Dylan; Simon & Garfunkel; Mothers of Invention; Velvet Underground), dies of a heart attack at 47
Keith Moon (1946-1978)
Sep 7 British rock drummer (The Who - "Bell Boy"), dies of a drug overdose at 32
- Sep 8 Leopoldo Torre Nilsson, Argentine film director (Monday's Child), dies at 54
- Sep 8 Pancho Vladigerov, Bulgarian pianist, composer (Vardar Rhapsody; Song to Peace), and pedagogue, dies at 79
- Sep 9 Hugh MacDiarmid [pen name for Christopher Murray Grieve], Scottish poet (leader of the Scottish literary renaissance), dies at 86
- Sep 9 Jack L Warner [Jacob Warner], Canadian-American film executive and president of the Warner Bros. Studios, dies at 86
- Sep 10 Ronnie Peterson, Swedish auto racer (World F1 C'ship runner-up 1971, 78), dies in crash during Italian F1 GP at 34
- Sep 11 Georgi Markov, Bulgarian writer and dissident, assassinated (probably stabbed by an umbrella with poison) by KGB and Bulgarian Secret Service in London at 49
- Sep 11 Janet Parker, English medical photographer, the last person to die of smallpox, dies at 40
- Sep 11 Mike Gazella, American baseball player (NY Yankees), dies at 82
- Sep 12 Frank Ferguson, American character actor (My Friend Flicka - "Gus"; Peyton Place - "Eli Carson"), dies of cancer at 71 (0r 78, birthdate disputed)
- Sep 15 Robert Cliche, French Canadian politician and judge (b. 1921)
- Sep 15 Willy Messerschmitt, German aircraft builder, dies at 80
- Sep 16 Bill Foster, American Baseball HOF pitcher (NgL All-Star 1933, 34; NgL World Series 1926, 27; Chicago American Giants), dies at 74
- Sep 19 Étienne Gilson, French philosopher and historian, dies at 94
- Sep 22 Lina Carstens, German actress (Homeland, Broken Jug), dies at 85
- Sep 23 Jay Adler, American actor (Macon County Line; Illegal, Big Combo), dies at 79
- Sep 24 Hasso von Manteuffel, German WWII general (5th Panzer Army) and politician, dies at 81
- Sep 24 Ruth Etting, American stage, radio, and screen singer ("Shine On Harvest Moon"; "Ten Cents A Dance"), and actress (Roman Scandals; Ziegfeld Follies), dies at 80
- Sep 24 Virginia Valli [McSweeney], American (mostly silent) film actress (Wild Oranges; Pleasure Garden), dies at 73
- Sep 25 Claire Adams, Canadian born silent film actress (Legally Dead, End of the Road), dies at 80
- Sep 26 Manne Siegbahn, Swedish physicist (Nobel 1924-discoveries and research in the field of X-ray spectroscopy), dies at 91
- Sep 28 John Paul I [Albino Luciano], 263rd Roman Catholic pope (1978), dies after 33 days as pope at 65
- Sep 30 Beryl Booker, American swing and cool jazz pianist (Dinah Washington), dies at 56
- Sep 30 Edgar Bergen, American ventriloquist (Charlie McCarthy), dies at 75
Assassination
Car Crash
Hanging
Killed in Action
Plane Crash
Poisoning