Granville Penn (9 December 1761 – 28 September 1844) was a great-grandson of Admiral Sir William Penn, a British author, and scriptural geologist.
He was born 9 December 1761 in Spring Gardens, London, the second surviving son of Thomas Penn and his wife, Lady Juliana Fermor Penn, fourth daughter of Thomas, first Earl of Pomfret. He studied at Magdalen College, Oxford, but did not complete his degree. He then became an assistant clerk in the war department.
In the period from 1788 Penn played a part in the development of veterinary education. A supporter of the Odiham Society, he met Charles Benoît Vial de Sainbel who was in England for the second time to try to set up a veterinary school, such as existed at Lyon; and whose profile was raised when he was asked to dissect the famous racehorse Eclipse. Penn ran a successful campaign over a few years to implement his own version of Sainbel's original scheme. The Veterinary College, London opened its doors to pupils at the beginning of 1792.
In 1834 Penn succeeded his brother, John Penn, in the estates of Stoke Park, Buckinghamshire, and Pennsylvania Castle, Portland.
He died at Stoke Park on 28 September 1844.. He had married Isabella, the eldest daughter of General Gordon Forbes and had 4 sons and 5 daughters.
Penn, fluent in French, Greek, Latin and Hebrew, was a Fellow of the Society of Antiquaries and wrote several books dealing with Biblical criticism and published a number of competent translations of ancient Greek works, including a critical revision of the English version of the New Testament. He also wrote some theological works particularly related to Biblical chronology (past and future) and the early history of post-Flood mankind. In 1833 he wrote the Life of Admiral Sir William Penn, on his great-grandfather.