John Freind (1675 – 26 July 1728), FRS, was an English physician.
He was younger brother of Robert Freind (1667–1751), headmaster of Westminster School, and was born at Croughton, Northamptonshire. He was under Richard Busby at Westminster School, and studied at Christ Church, Oxford under Henry Aldrich.
After this he began the study of medicine, and having proved his scientific attainments by various treatises was appointed a lecturer on chemistry at Oxford in 1704. In the following year he accompanied the English army, under Charles Mordaunt, 3rd Earl of Peterborough, into Spain. Shortly after his return in 1713 from Flanders, where he had accompanied British troops, he took up residence in London, where he soon obtained a reputation as a physician.
In 1716 he became a fellow of the Royal College of Physicians, delivered the Goulstonian Lectures in 1717, was chosen one of the censors in 1718 and Harveian orator in 1720. In 1722 he entered the House of Commons as Member of Parliament (MP) for Launceston in Cornwall; but, being suspected of favoring the cause of the exiled Stuarts, he spent half of that year in the Tower. In 1726 Freind was appointed physician to Queen Caroline, an office which he held till his death.