Shin'onsen (新温泉町, Shin'onsen-chō) is a town located in Mikata District, Hyōgo Prefecture, Japan.

In the Edo Period, it was divided between an area was controlled by Toyooka Domain, and by tenryo territory under direct administration of the Tokugawa shogunate.

Following the Meiji restoration, the villages of Onsen and Nishihama and were established within Mikata District with the creation of the modern municipalities system on April 1, 1889.

Shin'onsen has a mayor-council form of government with a directly elected mayor and a unicameral town council of 16 members.

In terms of national politics, the town is part of Hyōgo 5th district of the lower house of the Diet of Japan.