- Apr 1 Freddie Lennon, father of John Lennon (Beatles), dies at 63
- Apr 1 Max Ernst, German-French surrealist painter and sculptor (founded surrealism), dies at 85
- Apr 1 Miroslav Ponc, Czech composer, dies at 73
- Apr 1 Semyon Timoshenko, Russian marshal and army officer (most senior Russian officer on the front line in WWII), dies at 75
- Apr 2 Ray Teal, American actor (Judgment at Nuremberg, Bonanza), dies at 74
- Apr 3 Maurice Johnstone, English brass band composer, dies at 75
- Apr 4 Harry Nyquist, Swedish-American physicist and electronic engineer who contributed to communication theory (Nyquist–Shannon sampling theorem; Nyquist rate), dies at 87
Howard Hughes (1905-1976)
Apr 5 American reclusive billionaire, filmmaker and aviator, dies at 72
Wilder Penfield (1891-1976)
Apr 5 American-born Canadian neurosurgeon, dies at 85
- Apr 6 Ruth Plumly Thomson, American children's writer (Oz series), dies at 84
- Apr 6 Sidney Franklin, American bullfighter (b. 1903)
- Apr 7 Mary Margaret McBride, American radio personality (WOR-AM, NYC), dies at 76
- Apr 9 Akio Yashiro, Japanese composer, dies at 46
- Apr 9 Phil Ochs, American anti-war folk singer ("I Ain't Marching Anymore"; "Draft Dodger Rag"), commits suicide at 35
- Apr 11 Liam Dunn, American actor, dies at 59
- Apr 12 Paul Ford, American actor (Phil Silvers Show), dies at 74
- Apr 14 José Revueltas, Mexican write and political activist, dies after a heart attack at 61
- Apr 14 Maudie Prickett [Doyle], American character actress (Harvey; Hazel - "Rosie"), dies of renal failure at 61
- Apr 15 Gerald Smith, American antisemite (Nationalist Christian Crusade), dies at 78
- Apr 17 Henrik Dam, Danish biochemist, Nobel laureate (b. 1895)
- Apr 17 Jean-Jacques Gailliard, Belgian painter, dies at 85
- Apr 18 Mahmoud Younis, Suez Canal nationalization engineer, dies at 65
- Apr 22 Frutuoso de Lima Viana, Brazilian pianist & composer, dies at 79
- Apr 23 James Flavin, American actor (King Kong, In Cold Blood, Man With a Camera), dies from a ruptured aorta at 69
- Apr 23 Karl Schäfer, Austrian figure skater (Olympic gold 1932, 36), dies at 66
- Apr 23 Ronald Radd, British actor (King Lear, Up Jumped a Swagman), dies at 47
- Apr 23 Shimen Ruskin, Polish actor (Beau Brummel, Having a Wonderful Time), dies at 69
- Apr 24 Mark Tobey, US abstract painter, (Broadway Norm), dies at 85
- Apr 25 Alexander Brailowsky, Russian-French pianist (Chopin specialist), dies at 80
- Apr 25 Carol Reed, English film director (Agony & Ecstasy, Oliver!), dies at 69
- Apr 25 Margaret Bannerman, actress (Great Defender), dies at 79
- Apr 26 Allan Jackson, American newscaster (Youth Takes a Stand), dies at 60
- Apr 26 Neil McCallum, British-Canadian actor (Pete-Saber of London), dies at 45
- Apr 26 Sid James [Solomon Joel Cohen], South African-born British character & comedy actor (Hancock's Half Hour, Carry On), dies from a heart attack at 62
- Apr 28 Eugen Roth, German poet, dies at 81
- Apr 28 Richard Hughes, English writer (Fiction as Truth), dies at 76
- Apr 29 Wilhelm Maler, German composer, dies at 73
- Apr 30 Edvard Fliflet Braein, Norwegian composer (Ut mot havet (Out To Sea); Anne Pedersdotter), dies at 51
Assassination
Drug Overdose
Gunshot Wound
Murder
Plane Crash
Suicide