Chiswick (/ˈtʃɪzɪk/ ^ⓘ CHIZ-ik) is a district in West London, split between the London Boroughs of Hounslow and Ealing. It contains Hogarth's House, the former residence of the 18th-century English artist William Hogarth, Chiswick House, a neo-Palladian villa regarded as one of the finest in England and Fuller's Brewery, London's largest and oldest brewery. In a meander of the River Thames used for competitive and recreational rowing, with several rowing clubs on the river bank, the finishing post for the Boat Race is just downstream of Chiswick Bridge.

Old Chiswick was an ancient parish in the county of Middlesex, with an agrarian and fishing economy beside the river; from the Early Modern period, the wealthy built imposing riverside houses on Chiswick Mall. Having good communications with London, Chiswick became a popular country retreat and part of the suburban growth of London in the late 19th and early 20th centuries. It was made the Municipal Borough of Brentford and Chiswick in 1932 and part of Greater London in 1965, when it merged into the London Borough of Hounslow. Modern Chiswick is an affluent area which includes the early garden suburb Bedford Park, Grove Park, the Glebe Estate, Strand-on-the-Green and tube stations Chiswick Park, Turnham Green, and Stamford Brook, as well as the Gunnersbury Triangle local nature reserve. Some parts of Bedford Park and Acton Green are in the Chiswick W4 postcode area but the London Borough of Ealing. The main shopping and dining centre is Chiswick High Road.

Chiswick Roundabout is the start of the North Circular Road (A406). At Hogarth Roundabout, the Great West Road from central London becomes the M4 motorway, while the Great Chertsey Road (A316) runs south-west, becoming the M3 motorway.

People who have lived in Chiswick include the poets Alexander Pope and W. B. Yeats, the Italian poet and revolutionary Ugo Foscolo, the painters Vincent van Gogh and Camille Pissarro, the novelist E. M. Forster, the rock musicians Pete Townshend, John Entwistle, and Phil Collins, the stage director Peter Brook, and the actress Imogen Poots.

Chiswick was first recorded c. 1000 as the Old English Ceswican meaning 'Cheese Farm'; the riverside area of Duke's Meadows is thought to have supported an annual cheese fair up until the 18th century. The area was settled in Roman times; an urn found at Turnham Green contained Roman coins, and Roman brickwork was found under the Sutton manor house.

Old Chiswick grew up as a village around St Nicholas Church from c. 1181 on Church Street, its inhabitants practising farming, fishing and other riverside trades including a ferry, important as there were no bridges between London Bridge and Kingston throughout the Middle Ages. The area included three other small settlements, the fishing village of Strand-on-the-Green, the hamlet of Little Sutton in the centre, and Turnham Green on the west road out of London.

A decisive skirmish took place on Turnham Green early in the English Civil War. In November 1642, royalist forces under Prince Rupert, marching from Oxford to retake London, were halted by a larger parliamentarian force under the Earl of Essex. The royalists retreated and never again threatened the capital.

From 1758 until 1929 the Dukes of Devonshire owned Chiswick House, and their legacy can be found in street names all over Chiswick.