| Native Name: | 三口智也 |
| Nationality: | Japanese |
| Birth Date: | 26 April 1986 |
| Height: | 180 cm |
| Weight: | 67 kg |
| Sport: | Modern pentathlon |
| Club: | JSDF Physical Training School |
| Coach: | Hiroshi Miyagahara |
| Show-Medals: | yes |
is a Japanese modern pentathlete who won two team medals at the 2010 and 2014 Asian Games. He finished 22nd at the 2016 Olympics.
Miguchi started as a swimmer and competed for the national junior team. He changed to pentathlon in 2006, and in 2010 received the Japan Sports Award.