| Japan’s Prefecture | U.S. State | Date of Affiliation |
| Saitama | Ohio | 1990.10.22 |
| Japan’s Cities (Prefecture) | Ohio Cities | Date of Affiliation |
| Suzuka (Mie) | Bellefontaine | 1991.08.07 |
| Minami Awaji (Hyogo) | Celina | 1996.04.13 |
| Gifu (Gifu) | Cincinnati | 1988.05.11 |
| Oiso (Kanagawa) | Dayton | 1968.09.19 |
| Naraha (Fukushima) | Euclid | 1993.05.30 |
| Harima (Hyogo) | Lima | 1999.03.16 |
| Funehiki/Tamura (Fukushima) | Mansfield | 2000.10.21 |
| Yorii (Saitama) | Marysville | 2013.12.1 |
| Furukawa/Osaki (Miyagi) | Middletown | 1990.10.18 |
| Hachiman/Yawata (Kyoto) | Milan | 1986.08.12 |
| Awaji (Hyogo) | St. Marys | 1986.04.17 |
| Toyohashi (Aichi) | Toledo | 2000.04.29 |
| Takahashi(Okayama) | Troy | 1990.05.04 |
| Goshiki/Sumoto (Hyogo) | Van Wert | 1996.02.14 |
| Sayama (Saitama) | Worthington | 1999.11.01 |
| Friendship Cities (Prefecture) | Ohio Cities | Date of Affiliation |
| Mashiko (Tochigi) | Dublin | 2015.12.15 |
Information kindly provided by the Consulate General of Japan in Detroit
Ohio Association of Teachers of Japanese 