Alfred Beit (15 February 1853 – 16 July 1906) was an Anglo-German gold and diamond magnate in South Africa, and a major donor and profiteer of infrastructure development on the African continent. He also donated much money to university education and research in several countries, and was the "silent partner" who structured the capital flight from post-Boer War South Africa to Rhodesia. Beit's assets were structured around the so-called Corner House Group, which through its holdings in various companies controlled 37 per cent of the gold produced at the Witwatersrand's goldfields in Johannesburg in 1913.

Born and brought up in Hamburg, German Confederation, he was the eldest son and second of six children of an affluent Jewish-German citizen of Hamburg. His younger siblings included Otto Beit. Alfred Beit was an unpromising scholar and was apprenticed to Jules Porgès & Cie, the Amsterdam diamond firm where he developed a talent for examining stones.

Beit made his first fortune in property speculation in South Africa. Responding to a demand for business premises, he bought a piece of land and built twelve corrugated iron sheds for offices and rented eleven out monthly and kept one for himself. Twelve years later he sold the land for a considerable profit.

Beit was sent to Kimberly, Cape Colony in 1875 by his firm to buy diamonds—following the diamond strike at Kimberley. He became a business friend of Cecil Rhodes through his role in the Kimberley Central Company. Beit was captivated by Rhodes's talk of 'big schemes'. Together, they proceeded to buy out digging ventures and to eliminate opposition such as Barney Barnato. He rapidly became one of a group of financiers who gained control of the diamond-mining claims in the Central, Dutoitspan, and De Beers mines. Rhodes was the active politician and Beit provided a lot of the planning and financial backing.

Beit's diamond interests were mainly concentrated on Kimberley mine. He focused his main attention on the Kimberley Central Company aiming to expand its interests. He had a major role in the rise of Kimberley Central Company.

In 1886 Beit extended his interests to the newly discovered goldfields of the Witwatersrand and met with great success. In his business ventures there he made use of financiers Hermann Eckstein and Sir Joseph Robinson. He founded the Robertson Syndicate and the firm of Wernher, Beit & Co. He imported mining engineers from the US and was among the first to adopt deep-level mining. Rhodes purportedly was granted concessions by Lobengula, as a result of which Beit founded the British South Africa Company in 1888.

Beit became life-governor of De Beers and also a director of numerous other companies such as Rand Mines, Rhodesia Railways and the Beira Railway Company. His South-African assets formed the basis for the Corner House Group, which both controlled holding-companies like the Rand Mines and acted as an important network for several of the leading Randlords of the time.

In 1888 Beit moved to London when he felt he was better able to manage his financial empire and support Rhodes in his Southern African ambitions. Beit moved into Tewin Water, Tewin, near Welwyn, a large Regency house with Victorian additions and 7,000 acres (28 km²), and a few miles away Julius Wernher bought Luton Hoo, with 5,218 acres (21.1 km²). In the 1890s, he had a mansion built in Park Lane – Aldford House.