Mellette House, Historic house museum in Watertown, South Dakota, USA

The Mellette House is a two-story home and museum at 421 Fifth Avenue Northwest in Watertown, South Dakota, built by the Mellette family in 1885 on Prospect Hill, now called Mellette Hill. Inside are photographs of the Mellette family, original furniture and household items.

The Mellette family built the two-story house in 1885 on Prospect Hill, now Mellette Hill, and lived there until 1895. In 1929 it housed Watertown's first radio station. The house was condemned in 1943, after which a group bought the property and formed the Mellette Memorial Association to restore it. It joined the National Register of Historic Places in 1976.

The house is named for Arthur C. Mellette, South Dakota's first governor, who had it built in 1885 and lived there until 1895. Inside, photographs of the Mellette family hang alongside original furniture and household items, so a visit shows how the household was furnished rather than only how it was built.

The house is open to the public and located near downtown Watertown, making it relatively easy to reach. Visiting requires no special preparation, though checking operating hours in advance is recommended as they may be limited.

In 1929 the house hosted Watertown's first radio station, a use that ended long before the building was condemned in 1943. A group then bought the property and formed the Mellette Memorial Association, which still runs the site and gives free summer tours.