IKO - International Karate Organization - 15th All Japan Weight Category Karate Tournament (1998)
Kumite Lightweight
| Rang | Catégorie | Champion | Pays |
| 1 | Kumite Lightweight | Hiroyuki Kidachi | Japan |
| 2 | Kumite Lightweight | Koji Yasuda | Japan |
| 3 | Kumite Lightweight | Masafumi Tagahara | Japan |
| 4 | Kumite Lightweight | Shin Ito | Japan |
Kumite Middleweight
| Rang | Catégorie | Champion | Pays |
| 1 | Kumite Middleweight | Yuji Arai | Japan |
| 2 | Kumite Middleweight | Khosro Yaghoubi | Iran |
| 3 | Kumite Middleweight | Tadashi Honma | Japan |
| 4 | Kumite Middleweight | Makoto Yokoyama | Japan |
Kumite Heavyweight
| Rang | Catégorie | Champion | Pays |
| 1 | Kumite Heavyweight | Atsushi Kadoi | Japan |
| 2 | Kumite Heavyweight | Naoji Mikoshiba | Japan |
| 3 | Kumite Heavyweight | Keiichi Hayashi | Japan |
| 4 | Kumite Heavyweight | Masatoshi Kawaoka | Japan |
Kumite Super Heavyweight
| Rang | Catégorie | Champion | Pays |
| 1 | Kumite Super Heavyweight | Kiyoyuki Shida | Japan |
| 2 | Kumite Super Heavyweight | Yasuhiko Kimura | Japan |
| 3 | Kumite Super Heavyweight | Gun Irisawa | Japan |
| 4 | Kumite Super Heavyweight | Ryuta Noji | Japan |