John Butler (1717–1802) was an English bishop and controversialist.
Butler was born at Hamburg. As a young man he was a tutor in the family of Mr Child, a banker. He was not a member of either Cambridge or Oxford University, but in later life he received the degree of LL.D. from Cambridge.
He married first a lady who kept a school at Westminster; his second wife was the sister and coheiress of Sir Charles Vernon, of Farnham, Surrey, and this marriage improved his social standing. Having taken orders, he became a popular preacher in London, and in 1754 he published a sermon, preached at St Paul's Cathedral before the Sons of the Clergy. In the title-page, he is described as chaplain to the Princess Dowager of Wales. In the same year, he also published a sermon preached before the trustees of the Public Infirmary. He was installed as a prebendary of Winchester in 1760. In the title-page of a sermon preached before the House of Commons at St. Margaret's, Westminster, on the occasion of a general fast in 1758, he is described as minister of Great Yarmouth and chaplain to the Princess Dowager.
Despite this relationship to the princess's household, in 1762 he issued a political pamphlet addressed to the 'Cocoa Tree' (the Cocoa-Tree Club was associated with the Tories) and signed 'A Whig.' In this pamphlet, which ran to three editions, he bitterly attacked John Stuart, 3rd Earl of Bute and the conduct of his ministry since the accession of George III. He was appointed chaplain to Thomas Hayter, received the living of Everley, Wiltshire, and on the recommendation of Arthur Onslow was made one of the king's chaplains. In 1769 he was made archdeacon of Surrey.