Petworth House in Petworth, West Sussex, England, is a late 17th-century mansion, rebuilt in 1688 by Charles Seymour, 6th Duke of Somerset, and altered in the 1870s by Anthony Salvin. The site was previously occupied by a fortified manor house founded by Henry de Percy, the 13th-century chapel and undercroft of which still survive.

Today's building houses an important collection of paintings and sculptures, including 19 oil paintings by J. M. W. Turner (some owned by the family, some by Tate Britain), who was a regular visitor to Petworth, paintings by Van Dyck, carvings by Grinling Gibbons and Ben Harms, classical and neoclassical sculptures (including ones by John Flaxman and John Edward Carew), and wall and ceiling paintings by Louis Laguerre. There is also a terrestrial globe by Emery Molyneux, believed to be the only one in the world in its original 1592 state.

It stands in a 283-hectare (700-acre) landscaped park, known as Petworth Park, which was designed by 'Capability' Brown. The park is one of the more famous in England, largely on account of a number of pictures of it which were painted by Turner. It is inhabited by the largest herd of fallow deer in England. There is also a 12-hectare (30-acre) woodland garden, known as the Pleasure Ground.

Coordinates: 50°59′10″N 0°36′32″W / 50.986°N 0.609°W / 50.986; -0.609

Petworth is a small town and civil parish in the Chichester District of West Sussex, England. It is located at the junction of the A272 east-west road from Heathfield to Winchester and the A283 Milford to Shoreham-by-Sea road. Some twelve miles (21 km) to the south west of Petworth along the A285 road lies Chichester and the south-coast. The parish includes the settlements of Byworth and Hampers Green and covers an area of 2,690 hectares (6,644 acres). In 2001 the population of the parish was 2,775 persons living in 1,200 households of whom 1326 were economically active.

The town is mentioned in Domesday Book. It is best known as the location of the stately home Petworth House, the grounds of which (known as Petworth Park) are the work of Capability Brown. The house and its grounds are now owned and maintained by the National Trust.

In the early 17th century, the question of Petworth's status as an honour or a town came up when the Attorney General charged William Levett of Petworth, Gent., son of Anthony Levett, with "having unlawfully usurped divers privileges within the town of Petworth, which was parcel of the Honour of Arundel." William Levett's son Nicholas became rector of Westbourne, West Sussex.