Stadtmuseum Rapperswil, Municipal museum in Rapperswil-Jona, Switzerland.

Stadtmuseum Rapperswil-Jona occupies the Breny house, the 28-metre Breny tower and a connecting section of the medieval town wall on the Herrenberg, between Rapperswil Castle, the parish church and Engelplatz. The tower and house, built from 1492 for the knight Hans of Landenberg, keep late Gothic rooms such as the Breny and Landenberg chambers, and since 2010–2012 a new intermediate building links the two historic structures.

The core is a residential tower built in the early 13th century by the lords of Russikon, ministerials of the Counts of Rapperswil. Knight Hans of Landenberg rebuilt it in 1492; the Landenberg, Göldlin, Good and from 1758 Breny families followed. The museum opened in 1943, and the Breny sisters left the buildings to the town in 1958. After the "Janus" project, it was closed from January 2010 and reopened in October 2012 with a new intermediate building.

The museum keeps the late Gothic living hall and the Landenberg room of 1503 in their original condition, with wall paintings showing the coats of arms of the Landenberg and Hünenberg families from 1492. Sacred goldsmiths' work from the treasury of Rüti Abbey, dissolved in June 1525, is also on show.

The museum occupies the Breny house, the 28-metre Breny tower and a new connecting wing between the Stadtpfarrkirche and Engelplatz square. Entry and temporary exhibitions are in the new wing, which also links the two historic buildings; the city model of Rapperswil around 1800 and the medieval trades displays follow in the Breny house.

The first roses of Rapperswil bloom at the Breny tower and the parish church, because their medieval sandstone walls face the sun all year. The tower itself rises 28 metres on the Herrenberg, the castle hill that marked the town's medieval expansion to the northeast.