Burlington House is a building on Piccadilly in Mayfair, London. It was originally a private English Baroque and then Neo-Palladian mansion owned by the Earls of Burlington. It was significantly expanded in the mid-19th century after being purchased by the British government. Today, the Royal Academy and five learned societies occupy much of the building.

The house was one of the earliest of a number of very large private residences built on the north side of Piccadilly, previously a country lane, from the 1660s onwards. The first version was begun by Sir John Denham in about 1664. It was a red-brick double-pile hip-roofed mansion with a recessed centre, typical of the style of the time, or perhaps even a little old fashioned. Denham may have acted as his own architect, or he may have employed Hugh May, who certainly became involved in the construction after the house was sold in an incomplete state in 1667 to Richard Boyle, 1st Earl of Burlington, from whom it derives its name. Burlington had the house completed, which was the largest structure on his land, the Burlington Estate.

In 1704, the house was passed on to ten-year-old Richard Boyle, 3rd Earl of Burlington, who was to become the principal patron of the Neo-Palladian movement in England, and an architect in his own right. Around 1709, during Burlington's minority, Lady Juliana Boyle, the second Countess, commissioned James Gibbs to reconfigure the staircase and make exterior alterations to the house, including a quadrant Doric colonnade which was later praised by Sir William Chambers as "one of the finest pieces of architecture". The colonnade separated the house from increasingly urbanized Piccadilly with a cour d'honneur. Inside, Baroque decorative paintings in the entrance hall and a staircase by Sebastiano Ricci and Giovanni Antonio Pellegrini makes it one of the richest interiors in London.

In between his two Grand Tours of Italy (1714 and 1719), the 3rd Earl of Burlington's taste was transformed by the publication of Giacomo Leoni's Palladio, which made him develop a passion for Palladian architecture. In 1717 or 1718, the young Lord Burlington began making major modifications to Burlington House, and the supervision of the work was undertaken by Gibbs.

Later, Colen Campbell was appointed to replace Gibbs, who was working in the Baroque style of Sir Christopher Wren, to recast the work in a new manner on the old foundation. This was a key moment in the history of English architecture, as Campbell's work was in a strict Palladian style. The aesthetic preferences of Campbell and Burlington, soon joined by the aesthetic style of their close associate William Kent (who worked on interiors at Burlington House), were to provide the leading strain in English architecture and interior decoration for two generations.

Campbell's work closely followed the form of the previous building and reused much of the structure, but the conventional front (south) façade was replaced with an austere two-storey composition, taking Palladio's Palazzo Iseppo di Porti in Vicenza for a model but omitting sculpture and substituting a balustrade for the attic storey. The ground floor became a rusticated basement, which supported a monumental piano nobile of nine bays. This had no centrepiece but was highlighted by venetian windows in the projecting end bays, the first to be seen in England. Other alterations included a monumental screening gateway to Piccadilly and the reconstruction of most of the principal interiors, with typical Palladian features such as rich coved ceilings.

The Saloon, constructed immediately after William Kent's return from Rome in December 1719, has survived in the most intact condition; it was the first Kentian interior designed in England. Its plaster putti above the pedimented doorcases were probably by Giovanni Battista Guelfi.

Lord Burlington transferred his architectural energies to Chiswick House after 1722. Upon Burlington's death in 1753, Burlington House was passed on to the Dukes of Devonshire, but they had no need of it as they already owned Devonshire House just along Piccadilly. The fourth Duke's younger son Lord George Cavendish and a Devonshire in-law, William Cavendish-Bentinck, 3rd Duke of Portland, each used the house for at least two separate periods. Portland had some of the interiors altered by John Carr in the 1770s.