William FitzRoy

William FitzRoy may refer to:

• William FitzRoy, 3rd Duke of Cleveland (1698–1774), English nobleman
• William FitzRoy (British Army Officer) (1830–1902), British Army officer
• Lord William FitzRoy (1782–1857), British Royal Navy officer
• William FitzRoy, 6th Duke of Grafton (1819–1882), British peer and politician