Hyogo Prefecture Per Japanese census data,[4] the population of Minamiawaji has been declining steadily over the past 30 years.

Minamiawaji has a mayor-council form of government with a directly elected mayor and a unicameral city council of 20 members.

In terms of national politics, the city is part of Hyōgo 9th district of the lower house of the Diet of Japan.

Kibi International University's Faculty of Regional Creation Agriculture and the Kobe University Faculty of Maritime Sciences International Maritime Education and Research Center Awaji Marine Training Facility are located in Minamiawaji.

Jointly with Awaji and Sumoto, the city operates a low-cost electric bike rental scheme, designed to attract visitors to stay for more than one day in order to explore the island.