- Jetta: The Calling Series (Book 2)
- Jeu d'échecs sur Mars (Cycle de Mars n° 5)
- Jeune
- Jewel
- Jewel of The Stars - Season 1 Episode 2 - A New Reality
- Jewel of The Stars. Season 1 Episode 1: The Remnant
- Jewels of Gwahlur
- Jexx
- Jezebel (Daughter of Darkness): Jezebel's Journey, Book 1
- Jhyoti: Planetside
- Jie's World
- Jill Titan and the City of Robots
- Jill Titan and the Ghost Fleet
- Jill Titan and the Secret Weapon
- Jillia's Man, Gone Astray
- Jillia's Man, Regained
- Jim Héroe Galáctico
- Jimmy Stu Lives!
- Jimsy and the Monsters
- Jin-Bennu
- Jingo
- Jinian Footseer
- Jinian Star-Eye
- Jirel of Joiry
- Joan Darcy & The 27th Observer, The Telescope of Elsewhere
- Job, Herself
- Jocasta: Wife and Mother
- Joe & Bixby: Marked For Averageness
- Joe Calico in the Game: the Apprentice
- Joe Steele
- Joha: A World Apart
- John Calleghan & The PSI Pirates
- John Carter 1 : A Princes of Mars (Annotated)
- John Carter of Mars Series
- John Carter on Barsoom
- John Carter on Mars
- John Cold and the Weather Machine
- John Crusher P.I.: The Velvet Clad Hooker
- John Deer et l'origine des Sirènes
- John Gone
- John Kosichev
- John Mann: At Day's End
- John the Dreamer and the dagger of truth
- John's List
- Johnny Qwinn in the Attack of the Arachnids
- Johnny's Jaunt
- Johnny's Jaunt
- Johnny: Book 3 of the ROE Chronicles
- Joja
- Joker Moon
- Jokers Wild
- Jolie Blonde
- Jolly Roger
- Jonas Grinn
- Jonathan Parker and the Moan T'aye Ghost Dance
- Jonctions
- Jones kezében a világ
- Jordan
- Jordan's Deliverance
- Jordan's Fall
- Jordan's World
- Jornada Sem Limite
- Josh Anvil and the Gathering Storm
- Josh Anvil and the Indomitable Power
- Joshua
- Joss
- Jour de Pâques chez les Dragonnets
- Journals of the Plague Years
- Journey
- Journey and Jeopardy
- Journey Back To Threa
- Journey for the Souls
- Journey In Time to Cleopatra
- Journey Into the Flame
- Journey of a Battlemage
- Journey of the Pharaohs
- Journey Through the Mirror
- Journey to Andromeda
- Journey to Disappeared: Discovery
- Journey to Elvander
- Journey to Gone
- Journey To Light: Part I of the High Duties of Pacia
- Journey to Mars: The Denebian Connection
- Journey to Mars: The Vampire Underground
- Journey to the Andromeda Galaxy
- Journey To The Center Of Mars
- Journey to the Center of the Earth
- Journey to the Centre of the Earth
- Journey to the Stars
- Journey to Xanadu
- Journey to Yandol, and other stories
- Journey Towards Forever
- Journey With The Annoying
- Journey's End : An Asian Alternate-History Science Fiction Saga
- Journeys to the Center of Space
- Journeys to the Planet Mars or Our Mission to Ento
- Journeys With Stellarman
- Jouth Anthology vol 1
- Jouth # 3
- Jouth # 4
- Jouth Anthology: the Fantastic Flying Saucer Stories
- Jove
- Jovian
- Jubilation, U.S.A
- Judas Kiss
- Judas Unchained
- Judas' Gospel
- Judd's Errand
- Judgement Dave
- Judgment
- Judgment at Proteus
- Judgment Night: A Selection of Science Fiction
- Juggler of Worlds
- JUICE KIDS
- Jules Verne
- Jules Verne : Oeuvres complètes et annexes (annotées, illustrées)
- Jules Verne, le romancier de la science
- Jules Verne: The Collection (20.000 Leagues Under the Sea, Journey to the Interior of the Earth, Aro...
- Jules Verne’s Classic Collection:
- Julian
- Julio Verne
- July 57th
- Jump Tech
- Jumper
- Jumper: Griffin's Story
- Jumpers
- Jumpers 2
- Jumpship Hope
- June the Hunter
- Jungle Flame
- Jungle Ghoul Goddess
- Jungle Girl
- Jungle Jitters
- JUNGLE NOIRE-ILE DE FER
- Jungle Tales of Tarzan, Sixth Novel of the Tarzan Series
- Jungleland