| IGPX | September 15, 2003 | — | — |
| Iii Icecrin | April 6, 2021 | — | 24 |
| Ikebukuro West Gate Park | October 6, 2020 | — | 12 |
| Ikemen Sengoku: Bromances Across Time | July 12, 2017 | — | 12 |
| Iketeru Futari | February 2, 1999 | TBS Television | 16 |
| Ikki Tousen | July 30, 2003 | — | 49 |
| Ikkyū-san | October 15, 1975 | TV Asahi | 296 |
| Ikkyū-san | April 10, 1978 | — | 26 |
| Ikusa Otome Valkyrie | December 24, 2004 | — | 2 |
| Ikusa Otome Valkyrie 2 | September 26, 2008 | — | 3 |
| Ikusa Otome Valkyrie G | July 20, 2012 | — | 2 |
| Ikusa Otome Valkyrie Shinshō | February 24, 2006 | — | 2 |
| Imaizumin Chi wa Dōyara Gal no Tamariba ni Natteru Rashii | August 6, 2021 | — | 4 |
| Immoral Guild | October 5, 2022 | — | 12 |
| Immoral Sisters | April 27, 2001 | — | 3 |
| Immoral Sisters 2 | February 28, 2003 | — | 2 |
| Immoral Sisters: Blossoming | June 25, 2004 | — | 2 |
| In a World Full of Zombies I'm the Only One Who Doesn't Get Attacked | January 2027 | — | — |
| In Another World With My Smartphone | July 11, 2017 | AT-X | 24 |
| In Search of the Lost Future | October 4, 2014 | — | 12 |
| In the Beginning: The Bible Stories | November 30, 1992 | Rai 1, WOWOW | 26 |
| In the Clear Moonlit Dusk | January 11, 2026 | — | 12 |
| In the Heart of Kunoichi Tsubaki | April 10, 2022 | — | 13 |
| In the Land of Leadale | January 5, 2022 | — | 12 |
| In/Spectre | January 11, 2020 | — | 24 |
| Inakappe Taishō | October 4, 1970 | — | 104 |
| Inari, Konkon, Koi Iroha | January 15, 2014 | — | 10 |
| Inazuma Delivery | December 8, 2016 | — | — |
| Inazuma Eleven | October 5, 2008 | TV Tokyo | 127 |
| Inazuma Eleven Go | May 4, 2011 | TV Tokyo | 141 |
| Inazuma Eleven GO: Chrono Stone | — | — | — |
| Inazuma Eleven GO: Galaxy | — | — | — |
| Inazuma Eleven: Ares | April 6, 2018 | TX Network | 26 |
| Indian Summer | October 15, 2007 | — | 3 |
| Inexpressive Kashiwada and Expressive Oota | October 4, 2025 | — | 12 |
| Inferno Cop | December 24, 2012 | — | 13 |
| Infini-T Force | October 3, 2017 | — | 12 |
| Infinite Dendrogram | January 9, 2020 | — | 13 |
| Infinite Ryvius | October 6, 1999 | TV Tokyo | 26 |
| Infinite Stratos | January 7, 2011 | — | 26 |
| Ingoku Danchi | April 6, 2026 | BS11 | 12 |
| Ingress | October 18, 2018 | Fuji Television | 11 |
| Inherit the Winds | January 2027 | — | — |
| Initial D First Stage | April 19, 1998 | Fuji Television | 26 |
| Initial D Second Stage | October 15, 1999 | Fuji Television | 13 |
| Innocent Venus | July 26, 2006 | — | — |
| Insomniacs After School | April 11, 2023 | — | 13 |
| Interspecies Reviewers | January 11, 2020 | — | 12 |
| Interviews with Monster Girls | January 7, 2017 | — | 13 |
| Intrigue in the Bakumatsu – Irohanihoheto | October 6, 2006 | — | 26 |
| Inu × Boku SS | January 12, 2012 | — | 12 |
| Inugami-san to Nekoyama-san | April 10, 2014 | — | 12 |
| Inukami! | April 6, 2006 | TV Tokyo | 26 |
| Inuyasha | October 16, 2000 | Nippon Television Network System | 167 |
| Inuyasha: The Final Act | October 4, 2009 | Nippon Television Network System | 26 |
| Inuyashiki | October 12, 2017 | Fuji Television | 11 |
| Invaders of the Rokujouma!? | July 11, 2014 | — | 12 |
| Invincible King Tri-Zenon | October 14, 2000 | — | 22 |
| Invincible King Trider G7 | February 2, 1980 | — | 50 |
| Invincible Steel Man Daitarn 3 | June 3, 1978 | — | 40 |