Westonbirt House is a country house in Westonbirt, Gloucestershire, England, about 3 miles southwest of the town of Tetbury. It belonged to the Holford family from 1665 until 1926. The first house on the site was an Elizabethan manor house. The Holfords replaced it first with a Georgian house, and then Robert Stayner Holford, who inherited Westonbirt in 1839, replaced that house between 1863 and 1870 with the present mansion which was designed by Lewis Vulliamy. He also remodelled the gardens, diverted the main road and relocated the villagers.
The house is constructed of high quality ashlar masonry on a grand scale. The exterior is in an Elizabethan style, with a symmetrical main block and asymmetric wings, one of them containing a conservatory. The interiors are in a sumptuous classical style. The house was fitted with the latest technology such as gas lighting, central heating, fireproof construction and iron roofs. It is now a Grade I listed building.
Extensive formal terrace gardens were created around the house and 25 acres of ornamental woodlands were planted in the 19th century.