Bush House is a Grade II listed building at the southern end of Kingsway between Aldwych and the Strand in London, England. It was conceived as a major new trade centre by American industrialist Irving T. Bush, and commissioned, designed, funded, and constructed under his direction. The design was approved in 1919, work began in 1925, and was completed in 1935. Erected in stages, by 1929 Bush House was already declared the "most expensive building in the world".

Now part of the Strand Campus of King's College London, Bush House previously served as the headquarters of the BBC World Service. Broadcasting from Bush House lasted for 70 years, from winter 1941 to summer 2012. The final BBC broadcast from Bush House was the 12 noon BST news bulletin on 12 July 2012. The BBC World Service is now housed in Broadcasting House in Portland Place. King's College London has taken over the premises since acquiring the lease in 2015.

The longtime occupation of part of Bush House by HM Revenue and Customs (and its predecessor department the Inland Revenue) ended in March 2021 when it vacated the South-West Wing. This wing will also become a part of King's College London's Strand Campus, ensuring all wings of the building are now occupied by the University.

The building was commissioned, designed and originally owned by American individuals and companies. Irving T. Bush gained approval for his plans for the building in 1919, which was conceived as a major new trade centre and designed by American architect Harvey Wiley Corbett. The construction was undertaken by John Mowlem & Co.

Sections of Bush House were completed and opened over a period of 10 years: Centre Block was opened in 1925, North-West Wing in 1928, North-East Wing in 1929, South-East Wing in 1930, and South-West Wing in 1935. The full building complex was completed in 1935.

The building's opening ceremony was performed by Lord Balfour, Lord President of the Council, on 4 July 1925. It included the unveiling of two statues at the entrance made by American artist Malvina Hoffman. The statues symbolise Anglo-American friendship and the building bears the inscription "To the friendship of English speaking peoples". Built from Portland stone, Bush House was in 1929 declared the "most expensive building in the world".

The BBC European Service moved into the South-East Wing of Bush House after bombs damaged Broadcasting House on 8 December 1940 during The Blitz. The move was completed in 1941 and the BBC Overseas Service followed in 1958. The BBC World Service occupied four wings of the building.

In 1944 Bush House suffered external damage from a V-1 flying bomb.