Haus der Frau von Stein, Historical residence in Weimar, Germany.

Haus der Frau von Stein is a baroque three-wing residence in the old town of Weimar, built in the 18th century. The building sits close to other historic houses and presents the compact, multi-story form typical of urban homes built for the noble class of that period.

The building was erected between 1770 and 1773 by architect Anton Georg Hauptmann, during a period when the ducal court was actively developing the city. The ground floor originally served as military stables before the space was gradually adapted for other uses.

The house is named after Charlotte von Stein, who lived in the west wing from 1777 until her death in 1827 with her husband and three children; she never owned it. A memorial plaque on the facade recalls her. From 1779 to 1781 Goethe was her direct neighbour during the winter months, and theatre rehearsals for the ducal court took place inside.

The house stands at Ackerwand 25–27, its north side on Seifengasse, at the south-eastern edge of Weimar's old town. Two portals beside the short side wings mark the building's former division into separate parts. A memorial plaque to Charlotte von Stein is on the facade, and the fountain in front of the house dates from 1857.

In 1799, a chemical laboratory was set up on the ground floor by a German-Russian chemist, turning part of this noble house into a workspace for scientific experiments. Most visitors pass by without knowing that the same building once hosted both aristocratic life and hands-on research.