| Ōzato Castle 島添大里城 | |
| Location: | Nanjō, Okinawa |
| Open To Public: | yes |
| Type: | Gusuku |
| Built: | early 14th century |
| Builder: | Ōzato Magiri Aji |
| Materials: | Ryukyuan limestone, wood |
| Used: | early 14th century – 1429 |
| Condition: | Ruins |
| Controlledby: | Nanzan (1314–1429) Chūzan (1429) (1429–1879) (1879–1945) United States Military Government of the Ryukyu Islands(1945–1950) United States Civil Administration of the Ryukyu Islands(1950–1972)  Japan(1972–present) |
| Occupants: | Aji of Ōzato Magiri |
| Map Type: | Japan Okinawa Prefecture#Japan |
| Map Relief: | 1 |
, officially, is a Ryukyuan gusuku built in Nanzan and used until 1429. It, and the village of Ōzato, are named after the Ōzato Dynasty of Nanzan. It is in ruins, and is an officially designated historical site in Nanjō City, Okinawa.[1]
Nanzan was established in 1314 when the Lord of Shimajiri-Ōzato, Ōzato Ofusato, broke away from the chieftain Tamagusuku at Urasoe Castle. The castle was built in the 14th century West of the farming village of Ōzato, and became the seat of the Aji of Ōzato Magiri.[2] It fell into disuse after the capture of Nanzan Castle in 1429. During an excavation of the site, Chinese ceramics were found, showing the extensive trade that Nanzan had done with Ming China.[3] In 2012, Ōzato castle became an officially designated historical site on Okinawa Island.