| Kenka Bancho Otome: Girl Beats Boys | April 12, 2017 | — | 12 |
| Kenkō Zenrakei Suieibu Umishō | July 4, 2007 | — | 13 |
| Kenyū Densetsu Yaiba | April 9, 1993 | TV Tokyo | 52 |
| Kero Kero Chime | March 6, 1997 | — | 30 |
| Keshikasu-kun | January 4, 2010 | TV Tokyo | 44 |
| Ketchup: Cats Who Cook | October 5, 1998 | — | 65 |
| Ki Fighter Taerang | August 21, 2002 | Munhwa Broadcasting Corporation | 26 |
| Kiba | April 2, 2006 | TV Tokyo | 51 |
| Kick & Slide | July 7, 2021 | — | 12 |
| Kick no Oni | October 2, 1970 | — | 26 |
| Kick Off 2002 | February 18, 2002 | KBS 2TV, NHK Satellite 2 Television | 26 |
| Kiddy Girl-and | October 15, 2009 | — | 24 |
| Kiddy Grade | October 8, 2002 | Fuji Television | 24 |
| Kids on the Slope | April 12, 2012 | — | 12 |
| Kiitaro's Yokai Picture Diary | October 5, 2016 | — | 12 |
| Kikaider 01 The Animation | November 21, 2001 | — | 4 |
| Kiko-chan's Smile | October 5, 1996 | TBS Television | 51 |
| Kill Blue | April 11, 2026 | — | 12 |
| Kill la Kill | October 4, 2013 | — | 24 |
| Kill Me Baby | January 5, 2012 | TBS Television | 13 |
| Killed Again, Mr. Detective? | April 3, 2026 | — | 12 |
| Killing Bites | January 13, 2018 | — | 12 |
| Kimagure Orange Road | April 6, 1987 | Nippon Television | 48 |
| Kimagure Orange Road | March 1, 1989 | — | 8 |
| Kimba the White Lion | October 6, 1965 | Fuji Television | 52 |
| Kimi ga Aruji de Shitsuji ga Ore de | January 4, 2008 | — | 13 |
| Kimi ga Nozomu Eien: Next Season | December 21, 2007 | — | 4 |
| Kimi ni Todoke | October 6, 2009 | Nippon Television | 37 |
| Kimi to Boku | October 4, 2011 | TV Tokyo | 26 |
| Kimi to Fit Boxing | October 1, 2021 | Tokyo MX | 12 |
| KimiKiss: Pure Rouge | October 6, 2007 | — | 24 |
| Kin-iro Mosaic | July 6, 2013 | — | 24 |
| Kindergarten Wars | April 2027 | — | — |
| King Arthur | September 9, 1979 | Fuji Television | 30 |
| King Arthur: Prince on White Horse | April 6, 1980 | Fuji Television | 22 |
| King's Game The Animation | October 5, 2017 | — | 12 |
| King's Proposal | 2027 | — | — |
| King's Raid: Successors of the Will | October 3, 2020 | TV Tokyo | 26 |
| Kingdom | June 4, 2012 | NHK General TV | 77 |
| Kings of My Love | February 2011 | — | 14 |
| Kinkyū Hasshin Saver Kids | February 19, 1991 | — | 50 |
| Kinnikuman | April 3, 1983 | Nippon Television | 137 |
| Kino's Journey | April 8, 2003 | WOWOW | 13 |
| Kino's Journey: The Beautiful World - The Animated Series | October 6, 2017 | — | 12 |
| Kinokoinu: Mushroom Pup | October 3, 2024 | — | 12 |
| Kinpatsu no Jeanie | July 19, 1979 | TV Tokyo | 13 |
| KiraKira Pretty Cure a la Mode | February 5, 2017 | — | 49 |
| Kirarin Revolution | April 7, 2006 | TV Tokyo | 153 |
| Kiratto Pri Chan | April 8, 2018 | TX Network | — |
| Kirby: Right Back at Ya! | October 6, 2001 | CBC Television Co. | 100 |
| Kirio Fan Club | April 2, 2026 | — | 12 |
| Kishin Houkou Demonbane | May 18, 2006 | WOWOW | 12 |
| Kishin Taisen Gigantic Formula | April 4, 2007 | — | — |
| Kiss Him, Not Me | October 6, 2016 | TBS Television | 12 |
| Kiss×sis | December 22, 2008 | — | 12 |
| Kiss×sis | April 4, 2010 | — | 12 |
| Kiteretsu Daihyakka | March 27, 1988 | Fuji Television | 331 |
| Kiyo in Kyoto | February 25, 2021 | NHK Educational TV, NHK World-Japan | 12 |
| Kiznaiver | April 9, 2016 | Tokyo MX, Gunma Television | — |
| Kizuna no Allele | April 4, 2023 | — | 24 |