Sir William Vaughan (died 1649) was a cavalry officer in the armies of Charles I of England. Initially serving in Ireland during the Confederate Wars, the outbreak of the First English Civil War led to him being sent to England in 1644, at the head of an Anglo-Irish cavalry regiment, to reinforce the Royalist army. Appointed General of Horse for the area of Wales and the Marches, he was involved in a large number of battles and skirmishes in the north and west, including the defeat of the last Royalist field army at Stow, where he was wounded but escaped capture.