| Jikuu Yuten: Debias | Gil Galad | Role Playing > Action RPG | NES | Fully Playable | 1.0 | 26 Aug 2011 | EN |
| Jikkyou Power Pro Wrestling '96 - Max Voltage | Phil | Action > Fighting | SNES | Unfinished | 1.0 | 05 Jan 2008 | EN |
| Jikkyou Oshaberi Parodius | advancedpillow | Action > Shooter | SNES | Fully Playable | 1.0 | 09 Mar 2023 | EN |
| Jesus: Kyoufu no Bio Monster | Stardust Crusaders | Adventure | NES | Fully Playable | 3 Days Later Edition Rev 2 | 15 Aug 2016 | EN |
| Jelly Boy 2 | KingMike's Translations | Action > Platformer | SNES | Fully Playable | 1.0 | 16 Oct 2006 | EN |
| Janggun ui Adeul | pacnsacdave | Action > Fighting | NES | Fully Playable | 1.0 | 29 Jun 2015 | EN |
| Jajamaru no Daibouken | Stardust Crusaders | Action > Platformer | NES | Fully Playable | 1.0 | 10 Mar 2010 | EN |
| Jajamaru Ninpou Chou | Stardust Crusaders | Role Playing | NES | Fully Playable | 1.02 | 08 Dec 2020 | EN |
| Jajamaru Gekimaden: Maboroshi no Kinmajou | Stardust Crusaders | Role Playing > Action RPG | NES | Fully Playable | 1.0 | 08 Nov 2009 | EN |
| Jajamaru Gekimaden: Maboroshi no Kinmajou | Proveaux | Role Playing > Action RPG | NES | Addendum | 1.01 | 07 Apr 2016 | EN |
| Jajamaru Gekimaden: Maboroshi no Kinmajou | Ethereal Productions | Role Playing > Action RPG | NES | Unfinished | 0.10 | 15 Apr 2000 | EN |
| Jagur 5 | Django | Action Adventure | MSX | Fully Playable | 1 | 27 Mar 2021 | EN |
| Jabberwock no Hanayome | Non-Directional Translations | Action > Shooter | PC | Fully Playable | 1.0 | 16 Apr 2007 | EN |
| J.League Winning Eleven 10 + Europa League 06-07 | Fernando fk | Sports | PS2 | Fully Playable | 2.70 | 31 Jan 2007 | EN |
| J.League Live 64 | Zoinkity | Sports | N64 | Fully Playable | 1.0 | 21 Aug 2018 | EN |
| J.League Dynamite Soccer 64 | Zoinkity | Sports | N64 | Fully Playable | 1.0 | 20 Aug 2021 | EN |
| J-League: Winning Goal | Stardust Crusaders | Sports | NES | Fully Playable | 1.0 | 24 May 2009 | EN |
| Itadaki Street: Watashi no Mise ni Yottette | MrRichard999 | Boardgame | NES | Unfinished | 0.10b | 26 Feb 2016 | EN |
| Itadaki Street: Watashi no Mise ni Yottette | RType88 | Boardgame | NES | Unfinished | 0.3 | 24 Jan 2020 | EN |
| Ishin No Arashi | Hieroglitch | Simulation | NES | Unfinished | 0.7 | 24 Jan 2022 | EN |
