Three ships of the Royal Navy have borne the name HMS Royal William
HMS Royal William was a 100-gun first rate launched in 1670 as . She was rebuilt in 1692 and renamed HMS Royal William, rebuilt again in 1719, and rearmed to 84 guns and fitted as a guardship in 1790. She was broken up in 1813. HMS Royal William (1757) a cut down version of the above to create an 84-gun ship of the line built at Portsmouth and part of the Battle of Cape Spartel was a 120-gun first rate launched in 1833. She was fitted with screw propulsion and rearmed to 72 guns in 1860, and became a training ship named Clarence in 1885. She was burnt by accident in 1899.
See also RMS Royal William Scottish ship Royal William, a 32-gun fifth rate, renamed HMS Edinburgh when the Royal Scots Navy was merged into the Royal Navy by the Act of Union.