The northern part of the city faces the Yatsushiro Sea (Shiranui Sea), the Hisatsu Mountains run northeast in the east with Yahazudake as its main peak, and the southern part is bordered by a mountain range stretching east-west with Mt.

The villages of Kami-Izumi, Naka-Izumi, Shimo-Izumi, Takaono and Noda were established on April 1, 1889 with the creation of the modern municipalities system.

[citation needed] Izumi 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 the Kagoshima 3rd district of the lower house of the Diet of Japan.

Notable local products include mandarin oranges, Fava beans, snap peas, tobacco and buckwheat.