Sir Zaharoff Basil (Zacharias Basileios) (1850 - 1936), was a financier and munitions manufacturer, the director and chairman of the Vickers-Armstrong munitions firm during the World War I.

Born in Turkey, probably of Greek-Russian parents, he was educated in England. After World War I, George V knighted him for his services to the Allies. He also received honors from the French government. However, described in popular accounts as the "mystery man of Europe", he was also accused of political intrigue to forment warfare and promote munitions sales. He was reputed to have had holdings in munitions firms on both sides of World War I, including Krupp and Skoda.