Keith Rupert Murdoch ( MUR-dok; born 11 March 1931) is an Australian-born American investor and media propeitor. Through his company News Corp, he is the owner of hundreds of local, national, and international publishing outlets around the world, including in the UK (The Sun and The Times), in Australia (The Daily Telegraph, Herald Sun, and The Australian), in the US (The Wall Street Journal and the New York Post), book publisher HarperCollins, and the television broadcasting channels Sky News Australia and Fox News (through the Fox Corporation). He was also the owner of Sky (until 2018), 21st Century Fox (until 2019), and the now-defunct News of the World. With a net worth of US$21.7 billion as of 2 March 2022, Murdoch is the 31st richest person in the United States and the 71st richest in the world.

After his father's death in 1952, Murdoch took over the running of The News, a small Adelaide newspaper owned by his father. In the 1950s and 1960s, Murdoch acquired a number of newspapers in Australia and New Zealand before expanding into the United Kingdom in 1969, taking over the News of the World, followed closely by The Sun. In 1974, Murdoch moved to New York City, to expand into the US market; however, he retained interests in Australia and the UK. In 1981, Murdoch bought The Times, his first British broadsheet, and, in 1985, became a naturalized US citizen, giving up his Australian citizenship, to satisfy the legal requirement for US television network ownership.

In 1986, keen to adopt newer electronic publishing technologies, Murdoch consolidated his UK printing operations in London, causing bitter industrial disputes. His holding company News Corporation acquired Twentieth Century Fox (1985), HarperCollins (1989), and The Wall Street Journal (2007). Murdoch formed the British broadcaster BSkyB in 1990 and, during the 1990s, expanded into Asian networks and South American television. By 2000, Murdoch's News Corporation owned over 800 companies in more than 50 countries, with a net worth of over $5 billion.

In July 2011, Murdoch faced allegations that his companies, including the News of the World, owned by News Corporation, had been regularly hacking the phones of celebrities, royalty, and public citizens. Murdoch faced police and government investigations into bribery and corruption by the British government and FBI investigations in the US. On 21 July 2012, Murdoch resigned as a director of News International.

Many of Murdoch's papers and television channels have been accused of biased and misleading coverage to support his business interests and political allies, and some have credited his influence with major political developments in the UK, US, and Australia.