- Sep 1 Eero Saarinen, Finnish-American architect (Dulles Airport), dies at 51
- Sep 1 William Z. Foster, American labor organizer and US Communist Party president (1945-57), dies at 80
- Sep 2 Greet Koeman, Dutch opera soprano, dies at 54
- Sep 3 Robert E. Gross, American businessman (b. 1897)
- Sep 5 Ernest Bock, cricketer (Test for South Africa, 1935), dies
- Sep 7 Pieter Sjoerds Gerbrandy, Dutch lawyer and Prime Minister of the Netherlands (1940-45), dies at 76
- Sep 10 Leo Carrillo, American actor (American Empire, Cisco Kid), dies at 80
- Sep 10 Wolfgang von Trips, German racing driver, dies at 33
- Sep 12 Carl Hermann, German physicist, dies at 63
- Sep 16 A P F Chapman, cricketer (26 Tests for England), dies
- Sep 16 Yme Schuitmaker, Dutch potato farmer/dramatist, dies
Dag Hammarskjöld
Sep 18 Dag Hammarskjöld, Swedish public servant, 2nd Secretary-General of the United Nations (1953-61) and posthumous Nobel Peace Prize winner (1961), dies in a plane crash over Congo at 56
- Sep 19 Helen Kimble, fictional wife of Dr Richard Kimble (The Fugitive)
- Sep 19 Pieter Tesch, mine engineer/geology (Pedestal of Netherlands), dies
- Sep 19 Maurice Delage, French pianist, and composer (Ragamalika; Seven Haikais), dies at 81 [date of passing may be 21 Sept]
- Sep 21 Earle Dickson, American inventor (Band-Aid), dies at 68
- Sep 21 Maurice Delage, French composer, dies at 81
- Sep 22 Marion Davies, American actress (Not So Dumb, 5 & 10) and mistress of William Randolph Hearst, dies of cancer at 64
- Sep 23 Billy House, American actor (Imitation of Life; Bedlam; The Egg and I), dies at 71
- Sep 23 Elmer Diktonius, Finnish poet, composer, and musicologist (Janne Kubrik; Stenkol), dies at 65
- Sep 24 Sumner Welles, American diplomat (Good Neighbor Policy), dies at 68
- Sep 25 Frank Fay, American vaudeville comedian and actor (God's Gift to Women), dies at 69
- Sep 26 Eily Malyon, actress (Jane Eyre, I Married a Witch), dies at 81
- Sep 26 Juanita Hansen, actress (Fast Company), dies of heart ailment at 67
- Sep 26 Charles Erwin Wilson, American engineer (President and CEO of General Motors) and politician (United States Secretary of Defense 1953-57), dies at 71
- Sep 27 Hilda Doolittle, American poetess (Bid Me to Live), dies at 75
- Sep 28 Michael Shepley, British actor (Squibs, Dick & the Duchess), dies at 54
- Sep 29 Reinhard Herbig, German archaeologist, dies at 63
- Sep 30 Onésime Gagnon, Canadian politician, 20th Lieutenant Governor of Québec, dies at 72