Villa Grünfels, 19th century villa in Rapperswil-Jona, Switzerland.

Villa Grünfels is the former factory owner's villa of the Brändlin spinning mill, built in 1822 by Jakob and Rudolf Braendlin on a small Nagelfluh rock in Jona. Its south side has a double staircase and a Tuscan columned portico; the north approach climbs through a park-like slope. Two economy buildings face north toward the spinning mill.

Jakob Braendlin-Näf and his brother Rudolf had the villa built in 1822 as the factory owners' residence of the Brändlin spinning mill. After a fire in 1830 it was rebuilt, and in 1896 the merchant Wilhelm Stiefel-Diener acquired it. His adopted daughter Charlotte Stiefel, born 1898 and died 1986, bequeathed the property to the municipality of Jona on condition that it be made publicly accessible.

Charlotte Stiefel, who died in 1986, left the villa to the municipality of Jona on condition that it be opened to the public. Since then it has housed the Grünfels music school and a day centre for older people, and the cellar stage hosts cabaret and theatre.

The property and its exterior are visible from nearby, but access to the interior may be restricted. Visitors should check ahead about guided tours or special openings before planning a visit.

Charlotte Stiefel, adopted daughter of merchant Wilhelm Stiefel-Diener, bequeathed the villa to the municipality of Jona on condition that the grounds be opened to the public. That condition turned a former factory owner's home into a cultural house.