Reifenstein is a district of the municipality of Niederorschel at the foot of the middle Dün in Eichsfeld, Thuringia.

Reifenstein is the site of Reifenstein Monastery, founded in 1162. Count Ernst von Tonna-Gleichen founds the monastery in the same place. Villa Albolderode the Cistercian order. In 1803, the existing monastery was dissolved by Prussian cabinet order and converted into a state domain.