| Fighter | Record | Last Bout |
|---|---|---|
| Istela Nunes | 6-6-0 (1 NC) | 2025-04-05 |
| Iuri Alcantara | 35-10-0 (1 NC) | 2018-08-25 |
| Ivan Erslan | 15-6-0 (1 NC) | 2026-05-16 |
| Ivan Jorge | 27-7-0 | 2015-07-18 |
| Ivan Menjivar | 25-12-0 | 2014-03-01 |
| Ivan Salaverry | 14-9-0 | 2008-05-24 |
| Ivan Serati | 12-4-0 | 2009-01-17 |
| Ivana Petrovic | 7-3-0 | 2025-05-03 |
| Iwo Baraniewski | 9-0-0 | 2026-09-19 |
| Izabela Badurek | 6-3-0 | 2015-04-11 |
| James Irvin | 17-10-0 (2 NC) | 2010-08-01 |
| Kai Kamaka III | 18-8-1 | 2026-07-11 |
| Khadis Ibragimov | 8-4-0 | 2020-09-26 |
| Leandro Issa | 13-6-0 | 2016-09-03 |
| Minoki Ichihara | 0-1-0 | 1994-03-11 |
| Naoki Inoue | 11-1-0 | 2018-06-23 |
| Nassourdine Imavov | 17-4-0 (1 NC) | 2025-09-06 |
| Saygid Izagakhmaev | 22-4-0 | 2026-07-25 |
| Sean King III | 6-0-0 | 2026-09-12 |
| Teruto Ishihara | 10-7-2 | 2019-02-09 |
| Valeri Ignatov | 1-2-0 | 1999-09-24 |
| Wallid Ismail | 9-3-0 | 1997-02-07 |
| Yoislandy Izquierdo | 10-4-0 | 2012-07-07 |
| Zelim Imadaev | 8-3-0 | 2020-09-05 |