Books in Science Fiction (sorted alphabetically)
- Tulan C. C. MacApp
- Tunnel Under the World Frederik Pohl
- Turning Point Alfred Coppel
- Turnover Point Alfred Coppel
- Twelve Stories and a Dream H. G. Wells
- Twenty Thousand Leagues under the Sea Jules Verne
- Twenty Thousand Leagues Under the Sea Jules Verne
- Twenty Thousand Leagues Under the Seas: An Underwater Tour of the World Jules Verne
- Two Plus Two Makes Crazy Walter J. Sheldon
- Two Thousand Miles Below Charles Willard Diffin
- Two Timer Fredric Brown
- Two Weeks in August Frank M. Robinson
- Uller Uprising H. Beam Piper
- Ullr Uprising H. Beam Piper
- Ultimate Experiment Thornton DeKy
- Ultimate Weapon Jr. John W. Campbell
- Ultima Thule Mack Reynolds
- Unbegotten Child Winston K. Marks
- Unborn Tomorrow Mack Reynolds
- Under Arctic Ice Harry Bates
- Undersea Tube L. Taylor Hansen
- Under the Ocean to the South Pole; Or, the Strange Cruise of the Submarine Wonder Roy Rockwood
- Undetected George O. Smith
- Uniform of a Man Dave Dryfoos
- Universe — or Nothing Meyer Moldeven