Rüthen (German pronunciation: [ˈʁyːtn̩]) is a town in the district of Soest, in North Rhine-Westphalia, Germany.

Rüthen is situated at the northeastern border of the natural preserve Arnsberger Wald between the Haarstrang and the valley of the river Möhne, approx.

The area around Rüthen already belonged to the Erzbistum Köln (archbishopric Cologne) in the High Middle Ages.

On 29 September 1200 Rüthen was given town law by the sovereign, the archbishop of Cologne Adolf I. von Altena.

In the village of Kallenhardt you can find Schloss Körtlinghausen (1714), a small castle surrounded by water, a catholic church from 1722 and an old cityhall from the 14th or 15th century.