IKO - International Karate Organization - 8th All Japan Weight Category Karate Tournament (1991)
Kumite Lightweight
| Rang | Catégorie | Champion | Pays |
| 1 | Kumite Lightweight | Kensaku Yamamoto | Japan |
| 2 | Kumite Lightweight | Masanori Nagatomo | Japan |
| 3 | Kumite Lightweight | Naoki Kuniyoshi | Japan |
| 4 | Kumite Lightweight | Toru Sakata | Japan |
Kumite Middleweight
| Rang | Catégorie | Champion | Pays |
| 1 | Kumite Middleweight | Naoyuki Sonoda | Japan |
| 2 | Kumite Middleweight | Takhiroh Katoh | Japan |
| 3 | Kumite Middleweight | Eiji Kawamoto | Japan |
| 4 | Kumite Middleweight | Shinegori Sakamoto | Japan |
Kumite Heavyweight
| Rang | Catégorie | Champion | Pays |
| 1 | Kumite Heavyweight | Yoshihiro Tamura | Japan |
| 2 | Kumite Heavyweight | Yasuhiro Shichinohe | Japan |
| 3 | Kumite Heavyweight | Yutaka Ishi | Japan |
| 4 | Kumite Heavyweight | Hiroki Kurosawa | Japan |