| Name | Event | Round | Place | Time | Imp | FINA | ||
|---|---|---|---|---|---|---|---|---|
| 1 | Daiki YANAGAWA | 100 S Back | Prelims | 19th | 50.99 | +0.5% | 852 | |
| 2 | Yuya HINOMOTO | 50 S Breast | Prelims | 6th | 26.15 | +0.4% | 869 | |
| 3 | Katsuhiro MATSUMOTO | 100 S Free | Finals | – | 46.72 | +0.3% | R | 884 |
| 4 | Katsuhiro MATSUMOTO | 200 S Free | Prelims | 2nd | 1:41.29 | +2.4% | 944 | |
| 5 | Katsuhiro MATSUMOTO | 400 S Free | Finals | 4th | 3:36.87 | +0.5% | 937 | |
| 6 | Shogo TAKEDA | 1500 S Free | Timed Finals | 4th | 14:25.95 | +0.6% | 935 | |
| 7 | Ryota NAITOU | 200 S Back | Prelims | 7th | 1:50.78 | +0.2% | 867 | |
| 8 | Daiya SETO | 200 S Breast | Finals | 1st | 2:00.35 | +1.1% | 995 | |
| 9 | TEPPEI MORIMOTO | 200 S Fly | Prelims | 4th | 1:50.26 | +0.2% | 946 | |
| 10 | Takeshi KAWAMOTO | 50 S Back | Finals | – | 22.93 | +1.1% | R | 910 |