The Grade I listed building Walpole House is the largest, finest, and most complicated of the grand houses on Chiswick Mall, a waterfront street in the oldest part of Chiswick. Both the front wrought-iron screen and gate, and the back boundary wall, are Grade II listed.

The house was started in the Tudor era, with internal features surviving from the 16th and 17th centuries; the river frontage was built around 1730. The 0.5 hectares (1.2 acres) garden is listed in the English Heritage Register of Parks and Gardens.

Among Walpole House's famous inhabitants have been: Barbara, Duchess of Cleveland, mistress of King Charles II; Thomas Walpole; Daniel O'Connell; William Makepeace Thackeray; and Sir Herbert Beerbohm Tree.

The building that became Walpole House was built late in the Tudor era; internal features survive from the 16th and 17th centuries. The garden front was constructed around 1700, while the river frontage and the extension on the northwest side were added around 1730. It has three storeys, of brown bricks with red brick dressings. The front door is in a round-arched porch with Corinthian pilasters standing on plinths; above is an entablature. Its windows have double-hung sashes topped with flat arches.

The house is private and there is no access for the public.

In front of the house is an elegant Grade II* listed screen and wrought iron gate; the brick gateposts are topped with white globes, ball finials.

Walpole House garden is listed in the English Heritage Register of Parks and Gardens. It is L-shaped and of some 0.5 hectares (1.2 acres); it runs northwest from the house to the boundary wall at Netheravon Road, and is bordered by the back garden walls of The Tides and Thamescote House to the west, and Strawberry House to the east. At the back of the house is a terrace of York stone which occupies the full width of the house, as designed around 1926 by Mrs Robert Benson. Three steps rise to the lower lawn; a wide path paved with flagstones runs northwest across the lawn. The lower lawn is bordered by raised curved flowerbeds edged with flagstones; to the west of the stone path is a large mulberry tree. Five steps rise to the upper lawn, and the path crosses the upper garden. Above the stone wall separating the lawns are rosebeds. The upper garden has a pair of large poplar trees from Mrs Benson's design, and a large pond surrounded by flagstones and raised flowerbeds. The lawn ends at a 1997 yew hedge the full width of the garden; behind it, reached through two gaps in the hedge, is a wild garden containing large eucalyptus and Snakebark maple trees. Under the trees are flowers including cyclamens, euphorbias, and hellebores.

The back boundary wall is Grade II listed; it is described as "of plum-red brick about 9-10 ft high" with "some black headers". It tapers at the top and is capped with brick. The listing states that it is the remaining part of the boundary of College House, where the scholars of Westminster School came to escape the plague starting in 1557.