William Mahon
William Mahon may refer to:
- Sir William Mahon, 4th Baronet, of the Mahon baronets
- Sir William Mahon, 5th Baronet, of the Mahon baronets
- William D. Mahon, former coal miner who became president of the Amalgamated Association of Street Railway Employees of America
- Sir William Mahon, 7th Baronet, British Army officer