| Kizuna: Bonds of Love | — | — | — |
| Knight's & Magic | July 2, 2017 | — | 13 |
| Knights of Sidonia | April 11, 2014 | — | 24 |
| Knights of the Zodiac: Saint Seiya | July 19, 2019 | Netflix | 24 |
| Knyacki! | — | NHK Educational TV | — |
| Koala's Diary | October 2025 | — | — |
| Kobato | October 6, 2009 | NHK Satellite 2 Television | 24 |
| Kobo, the Li'l Rascal | October 19, 1992 | Nippon Television | 63 |
| Kocchi Muite! Miiko | February 14, 1998 | TV Asahi | 42 |
| KochiKame: Tokyo Beat Cops | 1996 | — | 367 |
| Kochoki | July 8, 2019 | — | 12 |
| Kodocha | April 5, 1996 | TV Tokyo | 102 |
| Kodomo no Jikan | October 12, 2007 | — | 12 |
| Kogepan | November 5, 2001 | — | 10 |
| Koi Kaze | April 1, 2004 | — | 13 |
| Koi Koi Seven | April 4, 2005 | — | 13 |
| Koi suru Tenshi Angelique | July 8, 2006 | — | — |
| Koihime Musō | July 9, 2008 | — | — |
| Koikimo | April 5, 2021 | — | 12 |
| Koishi Komeiji's Heart-Throbbing Adventure | June 28, 2009 | — | — |
| Koisuru One Piece | — | — | — |
| Kokkoku | January 8, 2018 | — | 12 |
| Kokoro Connect | July 8, 2012 | — | 13 |
| Kokoro Connect: Michi Random | November 19, 2012 | — | 4 |
| Kokoro Library | October 12, 2001 | — | 13 |
| Komekami! Girls | April 8, 2026 | — | 12 |
| Komi Can't Communicate | October 6, 2021 | TV Tokyo | 24 |
| Komori-san Can't Decline | October 4, 2015 | — | 12 |
| Kon'nichiwa Anne: Before Green Gables | April 5, 2009 | — | 39 |
| Kong: King of the Apes | April 15, 2016 | Netflix | 23 |
| Konna Ko Iru Kana | April 1986 | NHK | — |
| Kono Aozora ni Yakusoku o: Yōkoso Tsugumi Ryō e | April 4, 2007 | — | — |
| Kono Oto Tomare! Sounds of Life | April 6, 2019 | — | 26 |
| Konohana Kitan | October 4, 2017 | — | 12 |
| KonoSuba | January 13, 2016 | Tokyo MX | 31 |
| KonoSuba: An Explosion on This Wonderful World! | April 6, 2023 | — | 12 |
| Koro Sensei Quest! | December 23, 2016 | — | 12 |
| Koroshiya-san | October 10, 2013 | — | 10 |
| Kotaro Lives Alone | March 10, 2022 | Netflix | 10 |
| Kotencotenco | October 6, 2005 | — | 52 |
| Kotoura-san | January 11, 2013 | — | 12 |
| Koukou Butouden Crows | January 28, 1994 | — | 2 |
| KOWABON | October 4, 2015 | — | 13 |
| Kowloon Generic Romance | April 5, 2025 | — | — |
| Koyomimonogatari | January 10, 2016 | — | 12 |
| Kubikiri Cycle: Aoiro Savant to Zaregotozukai | October 26, 2016 | — | 8 |
| Kubo Won't Let Me Be Invisible | January 10, 2023 | — | 12 |
| Kujibiki Unbalance | December 22, 2004 | — | 3 |
| Kujibiki Unbalance | October 6, 2006 | Kids Station | 12 |
| Kujima: Why Sing, When You Can Warble? | April 9, 2026 | — | 12 |
| Kum-Kum | October 3, 1975 | MBS | 26 |
| Kuma Kuma Kuma Bear | October 7, 2020 | — | 24 |
| Kuma Miko: Girl Meets Bear | April 3, 2016 | — | 12 |
| Kunimatsu-sama no Otoridai | October 6, 1971 | — | 46 |
| Kunoichi Bakumatsu Kitan | — | — | — |
| Kunon the Sorcerer Can See | January 4, 2026 | — | 13 |
| Kurau Phantom Memory | June 24, 2004 | — | 24 |
| Kure-nai | April 3, 2008 | — | 12 |
| Kure-nai | July 2, 2010 | — | 2 |
| Kurogane Communication | October 5, 1998 | — | 24 |