Administratively it is divided into the city of Amami, the towns of Tatsugō, Setouchi, and the villages of Uken and Yamato in Kagoshima Prefecture.

Between 1571 and 1611, Amami Ōshima was briefly incorporated as part of the Ryukyu Kingdom as it expanded northwards along the archipelago.

To counter Ming authority, the island was invaded by samurai from Shimazu clan in 1609 and its incorporation into the official holdings of that domain was recognized by the Tokugawa shogunate in 1624.

Shimazu rule was harsh, with the inhabitants of the island reduced to serfdom and forced to raise sugar cane to meet high taxation, which often resulted in famine.

Saigō Takamori was exiled to Amami Ōshima in 1859, staying for two years, and his house has been preserved as a memorial museum.

After the Meiji Restoration Amami Ōshima was incorporated into Ōsumi Province and later became part of Kagoshima Prefecture.

Following World War II, along with the other Amami Islands, it was occupied by the United States until 1953, at which time it reverted to the control of Japan.

Since February 1974, a 7,861-hectare (19,420-acre) area that includes portions of the island and surrounding sea was protected as the Amami Gunto Quasi-national Park.

It absorbed the former Amami Gunto Quasi-national Park and other land and sea areas in adjacent municipalities.

The island is of volcanic origin, with Mount Yuwanda at 605 metres (1,985 ft) above sea level at its highest peak.

The Amami rabbit is sometimes called a living fossil because it represents an ancient Asian lineage that has elsewhere disappeared.

The economy of Amami Ōshima is based on agriculture (sugar cane, rice and sweet potatoes), commercial fishing, and the distillation of shōchū.

Traditional crafts on the island include the production of high quality hand-crafted silk called Ōshima-tsumugi which is mainly used to make kimono.