| Lakitu and...THE LOST LEVELS! | Gamet2004 | Super Mario Bros. | Action > Platformer | NES | G, L | Complete | 1.2 | 23 Mar 2021 |
| Lagoon - camera fix | Cyneprepou4uk | Lagoon | Role Playing > Action RPG | SNES | O | Improvement | 001 | 20 Dec 2022 |
| Lady Opera: Swf Panic | Darkdata | Super Mario Bros. | Action > Platformer | NES | G, L, T, GP | Complete | 2.0 | 25 Oct 2008 |
| La Liga Mexicana Nintendo Edition | Jerry Kalel Mtz. | J-League: Winning Goal | Sports | NES | G, T | Complete | 1.0 | 18 Jan 2021 |
| La guerra del golfo MMC-3 Hack | Wave | War in the Gulf | Action > Shooter | NES | O | Improvement | 1.0 | 16 May 2016 |
| Kyouryuu Sentai Zyuranger - No Full-Screen Flashes | Tetrahedrus | Kyoryu Sentai ZyuRanger | Action > Platformer | NES | O | Improvement | 1.0 | 03 Sep 2020 |
| Kyoro-chan Land: DMC Buzz Fix | TakuikaNinja | Castelian | Action > Platformer | NES | S | Bug Fix | 1.0 | 24 Nov 2022 |
| Kyatto Ninden Teyandee the Second Coming | Lomax | Kyattou Ninden Teyandee | Action > Platformer | NES | G, L, T, GP | Complete | 1.2 | 31 Dec 2012 |
| KuruKuru Fever Retail N64 Patch | Zoinkity | KuruKuru Fever | Puzzle | N64 | O | Improvement | 1.1 | 01 Sep 2021 |
| Kureji Lufia | Artemis | Lufia II: Rise of the Sinistrals | Role Playing | SNES | G, S, T, GP | Improvement | 6.1 | 15 May 2023 |
| Kunio Kun no Nekketsu Soccer League (Team Hack 2014) | Lipetsk | Kunio Kun no Nekketsu Soccer League | Sports | NES | GP | Improvement | 1.0 | 22 Nov 2014 |
| Kunio Kun no Nekketsu Soccer League (Team Hack 2014 - 4P on field + Fast AI) | Lipetsk | Kunio Kun no Nekketsu Soccer League | Sports | NES | GP | Improvement | 1.0 | 22 Nov 2014 |
| Kunio Kun no Nekketsu Soccer League (J) (Team Hack 2014 - 4P PK) | Lipetsk | Kunio Kun no Nekketsu Soccer League | Sports | NES | GP | Improvement | 1.0 | 22 Nov 2014 |
| Kunio Kun no Nekketsu Soccer League (J) (Team Hack 2014 - 2P PK) | Lipetsk | Kunio Kun no Nekketsu Soccer League | Sports | NES | GP | Improvement | 1.0 | 22 Nov 2014 |
| Kung-fu-man in Streets of Rage 2 | Metal64 | Streets of Rage 2 | Action > Beat 'Em Up | GEN | G, S, GP | Improvement | 1.0 | 30 Aug 2017 |
| Kung-Fu Heroes - Ninja Boy Edition | K.K. Drunkinski | Kung-Fu Heroes | Action > Beat 'Em Up | NES | G | Improvement | 1.0 | 28 Jul 2020 |
| Kung Fury: Streets of Rage 2 | Cakewarden | Streets of Rage 2 | Action > Beat 'Em Up | GEN | G, S | Improvement | 1.0 | 30 Oct 2016 |
| Kung Fu Heroes CNROM to MMC3 Hack | infidelity | Kung-Fu Heroes | Action > Beat 'Em Up | NES | O | Improvement | 1.0 | 03 Dec 2013 |
| Kung Fu Atarisized | Megafield64 | Kung Fu | Action > Beat 'Em Up | NES | G | Improvement | 1.0 | 02 Oct 2014 |
| Kuma and Panda's own stage | Szemigi | Tekken 3 | Action > Fighting | PSX | GP, O | Improvement | full | 12 Mar 2020 |
