William Mahon

William Mahon may refer to:


 * Sir William Mahon, 4th Baronet (1813–1893), of the Mahon baronets
 * Sir William Mahon, 5th Baronet (1856–1926), of the Mahon baronets
 * William D. Mahon (1861–1949), former coal miner who became president of the Amalgamated Association of Street Railway Employees of America
 * Sir William Mahon, 7th Baronet (born 1940), British Army officer