There is a ferry that runs between Nii Ōshima and Niihama approximately once every hour, taking fifteen minutes to complete a one-way journey.

At one point, there was the possibility that a bridge might be built to connect Ōshima and Shikoku, but these plans are now considered unlikely.

The island became Ōshima Village in Ehime Prefecture, with the establishment of the modern municipalities system on December 15, 1889.

Due to its rapidly aging population and its geographic isolation from Niihama and the main island of Shikoku, Nii Ōshima faces serious problems of rural depopulation.

The primary occupations on the island include shrimp farming and agriculture, particularly mikan and a distinctive type of white potato.