Charles Boyle, 4th Earl of Orrery KT PC FRS (28 July 1674 – 28 August 1731) was an English nobleman, statesman and patron of the sciences.
The second son of Roger Boyle, 2nd Earl of Orrery, and his wife Lady Mary Sackville (1647–1710), daughter of Richard Sackville, 5th Earl of Dorset, he was born at Little Chelsea, London. He was educated at Christ Church, Oxford, and soon distinguished himself by his learning and abilities. Like the first earl, he was an author, soldier and statesman. He translated Plutarch's life of Lysander, and published an edition of the epistles of Phalaris, which engaged him in the famous controversy with Bentley. He was a member of the Irish Parliament and sat for Charleville between 1695 and 1699. He was three times member for the town of Huntingdon; and on the death of his brother, Lionel, 3rd earl, in 1703, he succeeded to the title.
He entered the army, and in 1709 was raised to the rank of major-general, and sworn one of Her Majesty's Privy Council. He was appointed to the Order of the Thistle and appointed queen's envoy to the states of Brabant and Flanders; and having discharged this trust with ability, he was created an English peer, as Baron Boyle of Marston, in Somerset. He inherited the estate in 1714.