This is an odd list, arising in a vague question about who ought to come to mind as a significant SF/F writer from the 1950s. My assumptions are that some folks more often thought of as writers from the 40s and 60s published notable books in the 50s and some folks who were prominent in the 50s maybe aren’t so widely read today. So what I did to focus on people who had written a 50s “classic” was use Goodreads to look up ~125 people who wrote SF/F (generously defined and particularly including YA) novels in the 1950s and rank them by the number of people who had read each author’s most widely read novel. As usual, I’ve omitted the actual data from Goodreads.

1. J.R.R. Tolkien (The Fellowship of the Ring, 1954)
2. C.S. Lewis (The Lion, The Witch, and the Wardrobe, 1950)
3. Ray Bradbury (Fahrenheit 451, 1953)
4. Isaac Asimov (Foundation, 1951)
5. Robert A. Heinlein (Starship Troopers, 1959)
6. Arthur C. Clarke (Childhood’s End, 1953)
7. Kurt Vonnegut Jr. (The Sirens of Titan, 1959)
8. Walter M. Miller Jr. (A Canticle for Leibowitz, 1959)
9. John Wyndham (The Day of the Triffids, 1951)
10. Richard Matheson (I Am Legend, 1954)
11. Alfred Bester (The Stars My Destination, 1956)
12. Pat Frank (Alas, Babylon, 1959)
13. Nevil Shute (On the Beach, 1957)
14. Jack Finney (The Body Snatchers, 1955)
15. Theodore Sturgeon (More Than Human, 1953)
16. Clifford Simak (City, 1952)
17. Philip K. Dick (Time Out of Joint, 1959)
18. Frederik Pohl & C.M. Kornbluth (The Space Merchants, 1952)
19. Tove Jansson (Moominsummer Madness, 1954)
20. Jack Vance (The Dying Earth, 1950)
21. Hal Clement (Mission of Gravity, 1953)
22. John Christopher (The Death of Grass, 1956)
23. Stanislaw Lem (The Star Diaries, 1957)
24. James Blish (A Case of Conscience, 1958)
25. Brian Aldiss (Non-Stop, 1958)
26. Poul Anderson (The Broken Sword, 1954)
27. Andre Norton (The Time Traders, 1958)
28. A.E. Van Vogt (The Weapon Shops of Isher, 1951)
29. E.E. “Doc” Smith (First Lensman, 1950)
30. Fritz Leiber (The Big Time, 1958)
31. Fred Hoyle (The Black Cloud, 1957)
32. Eleanor Cameron (The Wonderful Flight to the Mushroom Planet, 1954)
33. Ward Moore (Bring the Jubilee, 1953)
34. Robert Sheckley (Immortality, Inc., 1959)
35. Leigh Brackett (The Long Tomorrow, 1955)
36. Fredric Brown (Martians, Go Home, 1954)
37. Eric Frank Russell (Wasp, 1957)
38. Mordecai Roshwald (Level 7, 1959)
39. Frank Herbert (Under Pressure, 1956)
40. Arkady & Boris Strugatsky (Country of the Crimson Clouds, 1959)
41. August Derleth (The Mask of Cthulhu, 1958)
42. Mark Clifton & Frank Riley (They’d Rather Be Right, 1954)
43. Edmond Hamilton (The City at World’s End, 1950)
44. Ivan Efremov (Andromeda, 1957)
45. Tom Godwin (The Survivors, 1958)
46. Kōbō Abe (Inter Ice Age 4, 1959)
47. Ernst Jünger (The Glass Bees, 1957)
48. H. Beam Piper (Uller Uprising, 1952)
49. Philip José Farmer (The Green Odyssey, 1957)
50. Algis Budrys (Who?, 1958)
51. C.M. Kornbluth (The Marching Morons, 1959)
52. Jay Williams & Raymond Abrashkin (Danny Dunn and the Anti-Gravity Paint, 1956)
53. H. Beam Piper & John J. McGuire (A Planet for Texans, 1957)
54. Alan E. Nourse (Star Surgeon, 1959)
55. Edgar Pangborn (A Mirror for Observers, 1958)
56. Vercors (Les Animaux dénaturés, 1952)
57. Philip Wylie (The Disappearance, 1951)
58. Bernard Wolfe (Limbo, 1952)
59. John D. MacDonald (Wine of the Dreamers, 1951)
60. Sarban (The Sound of His Horn, 1952)
61. Stefan Wul (Niourk, 1957)
62. Murray Leinster (The Forgotten Planet, 1954)
63. Robert Silverberg (Starman’s Quest, 1958)
64. Charles L. Harness (The Paradox Men, 1955)
65. L. Ron Hubbard (To the Stars, 1950)
66. Hugo Correa (Los altísimos, 1959)
67. Lester Del Rey (Nerves, 1956)
68. Ellen MacGregor (Miss Pickerell Goes to Mars, 1951)
69. Randall Garrett & Laurence M. Janifer (Brain Twister, 1959)
70. Jack Williamson & James E. Gunn (Star Bridge, 1955)
71. Wilson Tucker (The Long Loud Silence, 1952)
72. Frederik Pohl (Slave Ship, 1957)
73. L. Sprague de Camp (Rogue Queen, 1951)
74. Damon Knight (A for Anything, 1959)
75. Randall Garrett & Laurence M. Janifer (Pagan Passions, 1956)
76. Raymond F. Jones (This Island Earth, 1952)
77. Frank M. Robinson (The Power, 1956)
78. Fletcher Pratt (The Blue Star, 1952)
79. John W. Campbell (Islands of Space, 1956)
80. Donald A. Wollheim (The Secret of the Ninth Planet, 1959)
81. David Karp (One, 1953)
82. Charles Eric Maine (Alph, 1958)
83. Ben Bova (The Star Conquerors, 1959)
84. Chad Oliver (The Winds of Time, 1957)
85. Henry Kuttner & C.L. Moore (Mutant, 1953)
86. Edmund Cooper (Seed of Light, 1959)
87. Blake Savage (Rip Foster Rides the Gray Planet, 1952)
88. John Brunner (The World Swappers, 1959)
89. C.L. Moore (Judgment Night, 1952)
90. James Blish & Robert Lowndes (The Duplicated Man, 1959)
91. C.M. Kornbluth & Judith Merrill (Gunner Cade, 1952)
92. Jack Williamson (Seetee Ship, 1951)
93. George O. Smith (The Fourth R, 1959)
94. James E. Gunn (This Fortress World, 1955)
95. Judith Merrill (Shadow on the Hearth, 1950)
96. Rex Gordon (No Man Friday, 1956)
97. J.T. McIntosh (World Out of Mind, 1953)
98. Francis Rufus Bellamy (Atta, 1953)
99. E. Everett Evans (Man of Many Minds, 1953)
100. Joseph Greene (The Forgotten Star, 1959)
101. Robert Silverberg & Randall Garrett (Shrouded Planet, 1957)
102. Richard Marsten [Evan Hunter / Ed McBain] (Danger: Dinosaurs!, 1953)
103. John Lymington (Night of the Big Heat, 1959)
104. Angus MacVicar (The Lost Planet, 1953)
105. Allen A. Adler (Terror on Planet Ionus, 1957)
106. Islwyn Ffowc Elis (Wythnos Yng Nghymru Fydd, 1957)
107. Hugh Walters (First on the Moon, 1959)
108. Robert Crane (Hero’s Walk, 1952)
109. William Dexter (World in Eclipse, 1954)
110. Philip Latham (Missing Men of Saturn, 1953)
111. A.J. Merak (The Dark Millennium, 1959)
112. Patrick Moore (Mission to Mars, 1955)
113. F.L. Wallace (Address: Centauri, 1955)
114. Margaret St. Clair (Agent of the Unknown, 1956)
115. Stanton A. Coblentz (Into Plutonian Depths, 1950)
116. E.C. Eliott (Kemlo and the Zones of Silence, 1954)
117. Harold Mead (Mary’s Country, 1957)
118. Wallace West (The Bird of Time, 1959)
119. Curme Gray (Murder in Millennium VI, 1951)
120. Nat Schachner (Space Lawyer, 1953)
121. Perley Poore Sheehan (The Abyss of Wonders, 1953)
122. Robert Ardrey (The Brotherhood of Fear, 1957)
123. Eric Temple Bell (G.O.G. 666, 1954)
124. Lee Correy (Rocket Man, 1955)
125. René Ray (The Strange World of Planet X, 1957)