| Jimbo and the Jet Set | January 6, 1986 | BBC One | 25 |
| John Dillermand | 2021 | DR Ramasjang | — |
| Johnny Test | September 17, 2005 | The CW, Cartoon Network, The WB, Cartoon Network, CITV | 117 |
| JoJo's Circus | September 28, 2003 | Disney Channel | 59 |
| Jokie | — | RTL Telekids | 52 |
| José Totoy | — | — | 50 |
| Journey of Long | — | KBS 1TV | — |
| Julius Jr. | September 29, 2013 | Disney Jr. | 52 |
| Jungle Cubs | October 5, 1996 | American Broadcasting Company | 21 |
| Jungledyret Hugo | October 4, 2003 | TV 2 Danmark | 13 |
| Kaijudo | June 2, 2012 | — | 52 |
| Kamp Koral: SpongeBob's Under Years | March 4, 2021 | Nickelodeon | 26 |
| Karate Kommandos | September 15, 1986 | Boomerang | 5 |
| Kassai and Luk | April 30, 1997 | France 2 | 26 |
| Kate & Mim-Mim | September 1, 2014 | CBeebies, BBC Kids, Knowledge Kids | 49 |
| Katie and Orbie | 1994 | Family Channel | 78 |
| Kick Buttowski: Suburban Daredevil | February 13, 2010 | Disney XD | 52 |
| Kid Lucky | — | M6, M6 Kid, RaiPlay | — |
| Kid vs. Kat | October 25, 2008 | YTV | 52 |
| KikoRiki | May 17, 2004 | YouTube, TV Rain, Russia-1, Channel One Russia, Channel 31, STS, Russia-K, Domashny, Kinopoisk, Inter, Mir, K2+7 | 218 |
| Kikoriki: New Adventures | — | — | — |
| Kim Possible | June 7, 2002 | Disney Channel | 87 |
| Kindergarten: The Musical | September 3, 2024 | Disney Jr. | 15 |
| King Arthur's Disasters | April 11, 2005 | CITV | 26 |
| Kipper | September 5, 1997 | Walt Disney Television | 78 |
| Kitti Katz | May 18, 2023 | Netflix | 10 |
| Kunshikter | 2023 | — | 13 |
| Lady Lovely Locks | April 4, 1987 | — | 20 |
| Larryboy: The Cartoon Adventures | March 16, 2002 | — | 4 |
| Larva | March 26, 2011 | — | 275 |
| Lavender Castle | January 7, 1999 | ITV | 26 |
| Learning Time with Timmy | May 24, 2018 | — | 27 |
| Lego Elves: Secrets of Elvendale | September 1, 2017 | — | — |
| Leo & Tig | September 17, 2016 | Carousel, Mult | 78 |
| Leo da Vinci | 2019 | Rai Gulp, RaiPlay | 52 |
| Les Aventures de Colargol | 1968 | ORTF Télévision 2 | 53 |
| Les Kiwis | October 19, 2013 | — | 130 |
| Les Triplés | — | TF1, France 5 | 78 |
| Let's Go Luna! | November 21, 2018 | TVOKids, PBS Kids, Knowledge Kids | 64 |
| Let's Go, Bananas! | April 19, 2024 | Cartoon Network, CBC Kids, Sky Kids | 26 |
| Life with Louie | December 18, 1994 | Fox Broadcasting Company | 39 |
| Lifeboat Luke | — | — | — |
| Lil Glooscap and the Legends of Turtle Island | — | — | — |
| Lil' Elvis and the Truckstoppers | March 6, 1997 | ABC Television | 26 |
| Lillefinger | — | — | 26 |
| Lilo & Stitch: The Series | September 20, 2003 | Disney Channel | 65 |
| Lily's Driftwood Bay | May 5, 2014 | Nick Jr. | 100 |
| Little Bear | November 6, 1995 | Nickelodeon, CBC Television | 65 |
| Little Einsteins | October 9, 2005 | Playhouse Disney, Disney Channel | 67 |
| Little Ellen | September 13, 2021 | — | 20 |
| Little J & Big Cuz | — | National Indigenous Television | — |
| Little Lulu and Her Little Friends | October 3, 1976 | TV Asahi, National Educational Television | 26 |
| Little Monsters | September 14, 1998 | BBC One | 52 |
| Little Red Tractor | January 5, 2004 | Nickelodeon | 75 |
| Little Rosey | September 8, 1990 | American Broadcasting Company | 13 |
| Little Wizards | September 26, 1987 | American Broadcasting Company | 13 |
| Littlest Pet Shop | November 10, 2012 | TF1 | 104 |
| Lloyd in Space | February 3, 2001 | American Broadcasting Company | 39 |
| Looney Tunes Cartoons | May 27, 2020 | HBO Max | 82 |
| Los Peques | July 2002 | Flow | 22 |