| Kusoge-tte Iuna! | October 19, 2020 | — | 12 |
| Kusunoki's Flunking Her High School Glow-Up | — | — | — |
| Kusunoki's Garden of Gods | April 5, 2026 | — | 12 |
| Kuttsukiboshi | August 16, 2010 | — | 2 |
| Kuu Kuu Harajuku | November 1, 2015 | Nickelodeon, Nick Jr. Channel, 10 Comedy | 78 |
| Kyo Kara Maoh! | April 3, 2004 | NHK Satellite 2 Television | 117 |
| Kyo Kara Maoh! R | October 26, 2007 | — | 5 |
| Kyoro-chan | July 1, 1999 | TV Tokyo | 91 |
| Kyoshin to Hyōka no Shiro | August 8, 2020 | Nagasaki Culture Telecasting | 4 |
| Kyousougiga | October 2, 2013 | — | 10 |
| Kyō Kara Ore Wa!! | — | — | — |
| Kyō no Go no Ni | March 24, 2006 | — | 4 |
| Kyō no Go no Ni | October 5, 2008 | TV Tokyo | 13 |
| Kyōfu! Zombie Neko | October 2, 2015 | — | 52 |
| Kyōran Kazoku Nikki | April 12, 2008 | — | 26 |
| Kyūmei Senshi Nanosaver | — | — | — |
| Kämpfer | October 2, 2009 | TBS Television | 12 |
| Kämpfer für die Liebe | April 8, 2011 | — | 2 |
| Kōchū Ōja Mushiking: Mori no Tami no Densetsu | April 6, 2005 | — | — |
| Kōpen-chan | April 6, 2025 | — | — |
| Kōtetsu Sangokushi | April 5, 2007 | TV Tokyo | 25 |
| Kōtetsushin Jeeg | April 5, 2007 | WOWOW | 13 |
| Kōya no Shōnen Isamu | April 4, 1973 | Fuji Television | 52 |
| Kūchū Buranko | October 16, 2009 | Fuji Television | — |
| L'isola del Tesoro | November 22, 2016 | — | — |
| L/R: Licensed by Royalty | January 9, 2003 | — | 12 |
| La Casa de los Mañosos | July 27, 2026 | YouTube | 14 |
| La Corda d'Oro | October 1, 2006 | TV Tokyo, Nippon Television | 25 |
| La familia del barrio | — | — | 94 |
| La Linea | 1972 | RAI | 90 |
| La Seine no Hoshi | April 4, 1975 | Fuji Television | 39 |
| La storia della Arcana Famiglia | July 1, 2012 | — | 12 |
| Labyrinth of Flames | September 25, 2000 | — | 2 |
| Ladies versus Butlers! | January 5, 2010 | AT-X | 12 |
| Lady Georgie | April 9, 1983 | — | 45 |
| Lady Jewelpet | April 5, 2009 | — | 52 |
| Lady Lady!! | October 21, 1987 | TBS Television | 21 |
| Lady Lovely Locks | April 4, 1987 | — | 20 |
| Ladyspo | April 10, 2018 | — | — |
| Laff-A-Lympics | September 10, 1977 | American Broadcasting Company | 24 |
| Lagrange: The Flower of Rin-ne | January 8, 2012 | — | 24 |
| Laid-Back Camp | January 4, 2018 | — | 37 |
| Laku noć | February 8, 2005 | Nova TV | — |
| Lalabel, the Magical Girl | February 15, 1980 | — | 49 |
| Lalaloopsy | March 29, 2013 | Nickelodeon, Nick Jr. Channel | 52 |
| Lament of the Lamb | May 25, 2003 | — | 4 |
| Lamput | 2017 | Cartoon Network | 147 |
| Lamune | October 11, 2005 | — | 12 |
| Lance Dur | March 1, 2023 | Animation Digital Network | 7 |
| Lance N' Masques | October 1, 2015 | — | 12 |
| Land of the Lustrous | October 7, 2017 | — | 12 |
| Lapis Re:Lights | July 4, 2020 | — | 12 |
| Lapitch the Little Shoemaker | 2001 | — | 26 |
| Larryboy: The Cartoon Adventures | March 16, 2002 | — | 4 |
| Larva | March 26, 2011 | — | 275 |
| Lascars | 1998 | Canal+ | — |
| Lassie's Rescue Rangers | November 11, 1972 | American Broadcasting Company | 16 |
| Last Exile | April 8, 2003 | TV Tokyo | 26 |
| Last Exile: Fam, the Silver Wing | October 15, 2011 | — | 21 |
| Last Hope | April 4, 2018 | — | — |