John Perceval, 2nd Earl of Egmont PC, FRS (25 February 1711 – 4 December 1770) was a British politician, political pamphleteer, and genealogist who served as First Lord of the Admiralty.
He was the son and heir of John Perceval, 1st Earl of Egmont by his wife Catherine Parker, daughter of Sir Philip Parker, 2nd Baronet of Arwarton. He was baptised at the Palace of Westminster, London.
Perceval sat in the Irish House of Commons for Dingle between 1731 and 1749. In April 1748, he was created Lord of the Bedchamber to the Prince of Wales. He served as First Lord of the Admiralty from 1763 to 1766 and sat in the House of Commons for several constituencies.
From 1751 to 1757, he designed and created Enmore Castle at Enmore in Somerset, which received 'the dismissive mockery of Horace Walpole'.
Perceval married twice. His first marriage was on 15 February 1737 to Lady Catherine Cecil (died 16 August 1752, aged 33), who was the second daughter of James Cecil, 5th Earl of Salisbury. By her he had five sons and two daughters: