Ustroń [ˈustrɔɲ] ⓘ (German: Ustron) is a health resort town in Cieszyn Silesia, southern Poland.

The settlement was first mentioned in a Latin document of Diocese of Wrocław called Liber fundationis episcopatus Vratislaviensis from around 1305 as item in Ustrona.

[2][3][4] It meant that the village was in the process of location (the size of land to pay a tithe from was not yet precise).

The creation of the village was a part of a larger settlement campaign taking place in the late 13th century in the area that would later be known as Upper Silesia.

Politically, the village belonged initially to the Duchy of Teschen, formed in 1290 in the process of feudal fragmentation of Poland, and was ruled by a local branch of Piast dynasty.

When the steel work was closed in 1897 the market town switched to be more orientated towards a health and spa resort.